2.2.0.25truefalse06115 - Disclosure - Employee Retirement and Severance Benefits (Details 5)truefalseIn Millionsfalse1falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170PureStandardhttp://www.xbrl.org/2003/instancepurexbrli0JPYJPY¥2falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberPureStandardhttp://www.xbrl.org/2003/instancepurexbrli0JPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥3falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] 12/31/2008 JPY (¥) ¥BalanceAsOf_31Dec2008_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Memberhttp://www.sec.gov/CIK0000016988instant2008-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥1false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse1falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170PureStandardhttp://www.xbrl.org/2003/instancepurexbrli0JPYJPY¥2falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberPureStandardhttp://www.xbrl.org/2003/instancepurexbrli0JPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥3falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] 12/31/2008 JPY (¥) ¥BalanceAsOf_31Dec2008_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Memberhttp://www.sec.gov/CIK0000016988instant2008-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseJapanese plans [Member]2true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets3false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse460090000000460090falsetruefalsefalsefalse2truefalsefalse457208000000457208falsetruefalsefalsefalse3truefalsefalse429870000000429870falsetruefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets4false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse4falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Equity securites of Japanese Companies [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Equity_Securites_Of_Japanese_Companies_Member_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseEquity securites of Japanese Companies [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_EquitySecuritesOfJapaneseCompaniesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥5falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Equity securites of Japanese Companies [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Equity_Securites_Of_Japanese_Companies_Member_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseEquity securites of Japanese Companies [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_EquitySecuritesOfJapaneseCompaniesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseJapanese plans [Member] | Equity securites of Japanese Companies [Member]5true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets6false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse5017700000050177falsefalsefalsefalsefalse2truefalsefalse4884400000048844falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets7false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse6falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Equity securites of Japanese Companies [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 1 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Equity_Securites_Of_Japanese_Companies_Member_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Fair_Value_Inputs_Level1_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseEquity securites of Japanese Companies [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_EquitySecuritesOfJapaneseCompaniesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥7falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Equity securites of Japanese Companies [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 1 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Equity_Securites_Of_Japanese_Companies_Member_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Fair_Value_Inputs_Level1_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseEquity securites of Japanese Companies [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_EquitySecuritesOfJapaneseCompaniesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseJapanese plans [Member] | Equity securites of Japanese Companies [Member] | Fair Value, Inputs, Level 1 [Member]8true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets9false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse5017700000050177falsefalsefalsefalsefalse2truefalsefalse4884400000048844falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets10false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse8falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Equity securites of Japanese Companies [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 2 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Equity_Securites_Of_Japanese_Companies_Member_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Fair_Value_Inputs_Level2_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseEquity securites of Japanese Companies [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_EquitySecuritesOfJapaneseCompaniesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥9falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Equity securites of Japanese Companies [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 2 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Equity_Securites_Of_Japanese_Companies_Member_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Fair_Value_Inputs_Level2_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseEquity securites of Japanese Companies [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_EquitySecuritesOfJapaneseCompaniesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseJapanese plans [Member] | Equity securites of Japanese Companies [Member] | Fair Value, Inputs, Level 2 [Member]11true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets12false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalse2truefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets13false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse10falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Equity securites of Japanese Companies [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 3 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Equity_Securites_Of_Japanese_Companies_Member_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Fair_Value_Inputs_Level3_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseEquity securites of Japanese Companies [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_EquitySecuritesOfJapaneseCompaniesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥11falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Equity securites of Japanese Companies [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 3 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Equity_Securites_Of_Japanese_Companies_Member_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Fair_Value_Inputs_Level3_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseEquity securites of Japanese Companies [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_EquitySecuritesOfJapaneseCompaniesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseJapanese plans [Member] | Equity securites of Japanese Companies [Member] | Fair Value, Inputs, Level 3 [Member]14true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets15false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalse2truefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets16false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse12falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Equity Securites Of Foreign Companies [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Equity_Securites_Of_Foreign_Companies_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseEquity Securites of Foreign Companies [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_EquitySecuritesOfForeignCompaniesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥13falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Equity Securites Of Foreign Companies [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Equity_Securites_Of_Foreign_Companies_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseEquity Securites of Foreign Companies [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_EquitySecuritesOfForeignCompaniesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseJapanese plans [Member] | Equity Securites of Foreign Companies [Member]17true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets18false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse53520000005352falsefalsefalsefalsefalse2truefalsefalse54440000005444falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets19false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse14falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Equity Securites Of Foreign Companies [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 1 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Fair_Value_Inputs_Level1_Member_Equity_Securites_Of_Foreign_Companies_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseEquity Securites of Foreign Companies [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_EquitySecuritesOfForeignCompaniesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥15falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Equity Securites Of Foreign Companies [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 1 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Fair_Value_Inputs_Level1_Member_Equity_Securites_Of_Foreign_Companies_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseEquity Securites of Foreign Companies [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_EquitySecuritesOfForeignCompaniesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseJapanese plans [Member] | Equity Securites of Foreign Companies [Member] | Fair Value, Inputs, Level 1 [Member]20true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets21false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse53520000005352falsefalsefalsefalsefalse2truefalsefalse54440000005444falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets22false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse16falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Equity Securites Of Foreign Companies [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 2 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Fair_Value_Inputs_Level2_Member_Equity_Securites_Of_Foreign_Companies_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseEquity Securites of Foreign Companies [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_EquitySecuritesOfForeignCompaniesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥17falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Equity Securites Of Foreign Companies [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 2 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Fair_Value_Inputs_Level2_Member_Equity_Securites_Of_Foreign_Companies_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseEquity Securites of Foreign Companies [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_EquitySecuritesOfForeignCompaniesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseJapanese plans [Member] | Equity Securites of Foreign Companies [Member] | Fair Value, Inputs, Level 2 [Member]23true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets24false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalse2truefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets25false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse18falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Equity Securites Of Foreign Companies [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 3 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Fair_Value_Inputs_Level3_Member_Equity_Securites_Of_Foreign_Companies_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseEquity Securites of Foreign Companies [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_EquitySecuritesOfForeignCompaniesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥19falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Equity Securites Of Foreign Companies [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 3 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Fair_Value_Inputs_Level3_Member_Equity_Securites_Of_Foreign_Companies_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseEquity Securites of Foreign Companies [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_EquitySecuritesOfForeignCompaniesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseJapanese plans [Member] | Equity Securites of Foreign Companies [Member] | Fair Value, Inputs, Level 3 [Member]26true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets27false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalse2truefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets28false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse20falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Pooled Equity Funds [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Pooled_Equity_Funds_Member_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalsePooled Equity Funds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_PooledEquityFundsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥21falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Pooled Equity Funds [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Pooled_Equity_Funds_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalsePooled Equity Funds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_PooledEquityFundsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseJapanese plans [Member] | Pooled Equity Funds [Member]29true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets30false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse9059700000090597falsefalsefalsefalsefalse2truefalsefalse8535300000085353falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets31false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse22falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Pooled Equity Funds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 1 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Pooled_Equity_Funds_Member_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Fair_Value_Inputs_Level1_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalsePooled Equity Funds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_PooledEquityFundsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥23falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Pooled Equity Funds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 1 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Pooled_Equity_Funds_Member_Fair_Value_Inputs_Level1_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalsePooled Equity Funds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_PooledEquityFundsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseJapanese plans [Member] | Pooled Equity Funds [Member] | Fair Value, Inputs, Level 1 [Member]32true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets33false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalse2truefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets34false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse24falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Pooled Equity Funds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 2 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Pooled_Equity_Funds_Member_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Fair_Value_Inputs_Level2_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalsePooled Equity Funds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_PooledEquityFundsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥25falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Pooled Equity Funds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 2 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Pooled_Equity_Funds_Member_Fair_Value_Inputs_Level2_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalsePooled Equity Funds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_PooledEquityFundsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseJapanese plans [Member] | Pooled Equity Funds [Member] | Fair Value, Inputs, Level 2 [Member]35true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets36false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse9059700000090597falsefalsefalsefalsefalse2truefalsefalse8535300000085353falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets37false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse26falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Pooled Equity Funds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 3 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Pooled_Equity_Funds_Member_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Fair_Value_Inputs_Level3_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalsePooled Equity Funds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_PooledEquityFundsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥27falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Pooled Equity Funds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 3 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Pooled_Equity_Funds_Member_Fair_Value_Inputs_Level3_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalsePooled Equity Funds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_PooledEquityFundsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseJapanese plans [Member] | Pooled Equity Funds [Member] | Fair Value, Inputs, Level 3 [Member]38true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets39false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalse2truefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets40false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse28falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Government Bonds [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_U_S_Government_Agencies_Debt_Securities_Member_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseGovernment Bonds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_USGovernmentAgenciesDebtSecuritiesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥29falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Government Bonds [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_U_S_Government_Agencies_Debt_Securities_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseGovernment Bonds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_USGovernmentAgenciesDebtSecuritiesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseJapanese plans [Member] | Government Bonds [Member]41true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets42false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse96870000009687falsefalsefalsefalsefalse2truefalsefalse1480300000014803falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets43false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse30falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Government Bonds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 1 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_U_S_Government_Agencies_Debt_Securities_Member_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Fair_Value_Inputs_Level1_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseGovernment Bonds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_USGovernmentAgenciesDebtSecuritiesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥31falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Government Bonds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 1 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_U_S_Government_Agencies_Debt_Securities_Member_Fair_Value_Inputs_Level1_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseGovernment Bonds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_USGovernmentAgenciesDebtSecuritiesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseJapanese plans [Member] | Government Bonds [Member] | Fair Value, Inputs, Level 1 [Member]44true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets45false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse96870000009687falsefalsefalsefalsefalse2truefalsefalse1480300000014803falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets46false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse32falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Government Bonds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 2 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_U_S_Government_Agencies_Debt_Securities_Member_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Fair_Value_Inputs_Level2_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseGovernment Bonds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_USGovernmentAgenciesDebtSecuritiesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥33falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Government Bonds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 2 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_U_S_Government_Agencies_Debt_Securities_Member_Fair_Value_Inputs_Level2_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseGovernment Bonds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_USGovernmentAgenciesDebtSecuritiesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseJapanese plans [Member] | Government Bonds [Member] | Fair Value, Inputs, Level 2 [Member]47true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets48false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalse2truefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets49false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse34falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Government Bonds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 3 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_U_S_Government_Agencies_Debt_Securities_Member_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Fair_Value_Inputs_Level3_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseGovernment Bonds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_USGovernmentAgenciesDebtSecuritiesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥35falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Government Bonds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 3 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_U_S_Government_Agencies_Debt_Securities_Member_Fair_Value_Inputs_Level3_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseGovernment Bonds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_USGovernmentAgenciesDebtSecuritiesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseJapanese plans [Member] | Government Bonds [Member] | Fair Value, Inputs, Level 3 [Member]50true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets51false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalse2truefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets52false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse36falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Municipal Bonds [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Municipal_Bonds_Member_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseMunicipal Bonds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MunicipalBondsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥37falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Municipal Bonds [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Municipal_Bonds_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseMunicipal Bonds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MunicipalBondsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseJapanese plans [Member] | Municipal Bonds [Member]53true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets54false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse323000000323falsefalsefalsefalsefalse2truefalsefalse879000000879falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets55false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse38falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Municipal Bonds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 1 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Municipal_Bonds_Member_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Fair_Value_Inputs_Level1_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseMunicipal Bonds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MunicipalBondsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥39falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Municipal Bonds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 1 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Municipal_Bonds_Member_Fair_Value_Inputs_Level1_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseMunicipal Bonds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MunicipalBondsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseJapanese plans [Member] | Municipal Bonds [Member] | Fair Value, Inputs, Level 1 [Member]56true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets57false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalse2truefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets58false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse40falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Municipal Bonds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 2 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Municipal_Bonds_Member_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Fair_Value_Inputs_Level2_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseMunicipal Bonds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MunicipalBondsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥41falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Municipal Bonds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 2 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Municipal_Bonds_Member_Fair_Value_Inputs_Level2_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseMunicipal Bonds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MunicipalBondsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseJapanese plans [Member] | Municipal Bonds [Member] | Fair Value, Inputs, Level 2 [Member]59true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets60false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse323000000323falsefalsefalsefalsefalse2truefalsefalse879000000879falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets61false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse42falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Municipal Bonds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 3 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Municipal_Bonds_Member_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Fair_Value_Inputs_Level3_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseMunicipal Bonds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MunicipalBondsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥43falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Municipal Bonds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 3 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Municipal_Bonds_Member_Fair_Value_Inputs_Level3_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseMunicipal Bonds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MunicipalBondsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseJapanese plans [Member] | Municipal Bonds [Member] | Fair Value, Inputs, Level 3 [Member]62true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets63false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalse2truefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets64false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse44falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Corporate Bonds [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Corporate_Bond_Securities_Member_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseCorporate Bonds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CorporateBondSecuritiesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥45falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Corporate Bonds [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Corporate_Bond_Securities_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseCorporate Bonds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CorporateBondSecuritiesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseJapanese plans [Member] | Corporate Bonds [Member]65true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets66false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse65180000006518falsefalsefalsefalsefalse2truefalsefalse76650000007665falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets67false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse46falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Corporate Bonds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 1 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Corporate_Bond_Securities_Member_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Fair_Value_Inputs_Level1_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseCorporate Bonds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CorporateBondSecuritiesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥47falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Corporate Bonds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 1 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Corporate_Bond_Securities_Member_Fair_Value_Inputs_Level1_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseCorporate Bonds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CorporateBondSecuritiesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseJapanese plans [Member] | Corporate Bonds [Member] | Fair Value, Inputs, Level 1 [Member]68true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets69false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalse2truefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets70false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse48falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Corporate Bonds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 2 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Corporate_Bond_Securities_Member_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Fair_Value_Inputs_Level2_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseCorporate Bonds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CorporateBondSecuritiesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥49falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Corporate Bonds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 2 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Corporate_Bond_Securities_Member_Fair_Value_Inputs_Level2_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseCorporate Bonds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CorporateBondSecuritiesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseJapanese plans [Member] | Corporate Bonds [Member] | Fair Value, Inputs, Level 2 [Member]71true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets72false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse65180000006518falsefalsefalsefalsefalse2truefalsefalse76650000007665falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets73false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse50falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Corporate Bonds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 3 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Corporate_Bond_Securities_Member_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Fair_Value_Inputs_Level3_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseCorporate Bonds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CorporateBondSecuritiesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥51falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Corporate Bonds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 3 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Corporate_Bond_Securities_Member_Fair_Value_Inputs_Level3_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseCorporate Bonds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CorporateBondSecuritiesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseJapanese plans [Member] | Corporate Bonds [Member] | Fair Value, Inputs, Level 3 [Member]74true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets75false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalse2truefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets76false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse52falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Pooled Debt Funds [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Pooled_Debt_Funds_Member_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalsePooled Debt Funds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_PooledDebtFundsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥53falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Pooled Debt Funds [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Pooled_Debt_Funds_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalsePooled Debt Funds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_PooledDebtFundsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseJapanese plans [Member] | Pooled Debt Funds [Member]77true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets78false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse194286000000194286falsefalsefalsefalsefalse2truefalsefalse189870000000189870falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets79false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse54falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Pooled Debt Funds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 1 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Pooled_Debt_Funds_Member_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Fair_Value_Inputs_Level1_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalsePooled Debt Funds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_PooledDebtFundsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥55falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Pooled Debt Funds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 1 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Pooled_Debt_Funds_Member_Fair_Value_Inputs_Level1_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalsePooled Debt Funds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_PooledDebtFundsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseJapanese plans [Member] | Pooled Debt Funds [Member] | Fair Value, Inputs, Level 1 [Member]80true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets81false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalse2truefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets82false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse56falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Pooled Debt Funds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 2 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Pooled_Debt_Funds_Member_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Fair_Value_Inputs_Level2_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalsePooled Debt Funds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_PooledDebtFundsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥57falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Pooled Debt Funds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 2 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Pooled_Debt_Funds_Member_Fair_Value_Inputs_Level2_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalsePooled Debt Funds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_PooledDebtFundsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseJapanese plans [Member] | Pooled Debt Funds [Member] | Fair Value, Inputs, Level 2 [Member]83true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets84false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse194286000000194286falsefalsefalsefalsefalse2truefalsefalse189870000000189870falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets85false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse58falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Pooled Debt Funds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 3 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Pooled_Debt_Funds_Member_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Fair_Value_Inputs_Level3_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalsePooled Debt Funds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_PooledDebtFundsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥59falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Pooled Debt Funds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 3 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Pooled_Debt_Funds_Member_Fair_Value_Inputs_Level3_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalsePooled Debt Funds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_PooledDebtFundsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseJapanese plans [Member] | Pooled Debt Funds [Member] | Fair Value, Inputs, Level 3 [Member]86true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets87false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalse2truefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets88false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse60falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Mortgage Backed Securities and other asset backed securities [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Mortgage_Backed_Securities_And_Other_Asset_Backed_Securities_Member_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseMotgage backed securities (and other asset backed securities)us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_MortgageBackedSecuritiesAndOtherAssetBackedSecuritiesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥61falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Mortgage Backed Securities and other asset backed securities [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Mortgage_Backed_Securities_And_Other_Asset_Backed_Securities_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseMotgage backed securities (and other asset backed securities)us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_MortgageBackedSecuritiesAndOtherAssetBackedSecuritiesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseJapanese plans [Member] | Motgage backed securities (and other asset backed securities)89true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets90false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse19800000001980falsefalsefalsefalsefalse2truefalsefalse943000000943falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets91false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse62falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Mortgage Backed Securities and other asset backed securities [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 1 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Mortgage_Backed_Securities_And_Other_Asset_Backed_Securities_Member_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Fair_Value_Inputs_Level1_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseMotgage backed securities (and other asset backed securities)us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_MortgageBackedSecuritiesAndOtherAssetBackedSecuritiesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥63falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Mortgage Backed Securities and other asset backed securities [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 1 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Mortgage_Backed_Securities_And_Other_Asset_Backed_Securities_Member_Fair_Value_Inputs_Level1_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseMotgage backed securities (and other asset backed securities)us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_MortgageBackedSecuritiesAndOtherAssetBackedSecuritiesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseJapanese plans [Member] | Motgage backed securities (and other asset backed securities) | Fair Value, Inputs, Level 1 [Member]92true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets93false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalse2truefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets94false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse64falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Mortgage Backed Securities and other asset backed securities [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 2 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Mortgage_Backed_Securities_And_Other_Asset_Backed_Securities_Member_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Fair_Value_Inputs_Level2_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseMotgage backed securities (and other asset backed securities)us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_MortgageBackedSecuritiesAndOtherAssetBackedSecuritiesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥65falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Mortgage Backed Securities and other asset backed securities [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 2 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Mortgage_Backed_Securities_And_Other_Asset_Backed_Securities_Member_Fair_Value_Inputs_Level2_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseMotgage backed securities (and other asset backed securities)us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_MortgageBackedSecuritiesAndOtherAssetBackedSecuritiesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseJapanese plans [Member] | Motgage backed securities (and other asset backed securities) | Fair Value, Inputs, Level 2 [Member]95true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets96false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse19800000001980falsefalsefalsefalsefalse2truefalsefalse943000000943falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets97false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse66falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Mortgage Backed Securities and other asset backed securities [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 3 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Mortgage_Backed_Securities_And_Other_Asset_Backed_Securities_Member_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Fair_Value_Inputs_Level3_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseMotgage backed securities (and other asset backed securities)us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_MortgageBackedSecuritiesAndOtherAssetBackedSecuritiesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥67falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Mortgage Backed Securities and other asset backed securities [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 3 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Mortgage_Backed_Securities_And_Other_Asset_Backed_Securities_Member_Fair_Value_Inputs_Level3_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseMotgage backed securities (and other asset backed securities)us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_MortgageBackedSecuritiesAndOtherAssetBackedSecuritiesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseJapanese plans [Member] | Motgage backed securities (and other asset backed securities) | Fair Value, Inputs, Level 3 [Member]98true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets99false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalse2truefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets100false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse68falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Life insurance company general accounts [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Life_Insurance_Company_General_Accounts_Member_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseLife insurance company general accounts [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_LifeInsuranceCompanyGeneralAccountsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥69falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Life insurance company general accounts [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Life_Insurance_Company_General_Accounts_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseLife insurance company general accounts [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_LifeInsuranceCompanyGeneralAccountsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseJapanese plans [Member] | Life insurance company general accounts [Member]101true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets102false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse9161000000091610falsefalsefalsefalsefalse2truefalsefalse9426900000094269falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets103false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse70falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Life insurance company general accounts [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 1 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Life_Insurance_Company_General_Accounts_Member_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Fair_Value_Inputs_Level1_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseLife insurance company general accounts [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_LifeInsuranceCompanyGeneralAccountsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥71falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Life insurance company general accounts [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 1 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Life_Insurance_Company_General_Accounts_Member_Fair_Value_Inputs_Level1_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseLife insurance company general accounts [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_LifeInsuranceCompanyGeneralAccountsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseJapanese plans [Member] | Life insurance company general accounts [Member] | Fair Value, Inputs, Level 1 [Member]104true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets105false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalse2truefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets106false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse72falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Life insurance company general accounts [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 2 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Life_Insurance_Company_General_Accounts_Member_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Fair_Value_Inputs_Level2_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseLife insurance company general accounts [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_LifeInsuranceCompanyGeneralAccountsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥73falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Life insurance company general accounts [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 2 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Life_Insurance_Company_General_Accounts_Member_Fair_Value_Inputs_Level2_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseLife insurance company general accounts [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_LifeInsuranceCompanyGeneralAccountsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseJapanese plans [Member] | Life insurance company general accounts [Member] | Fair Value, Inputs, Level 2 [Member]107true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets108false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse9161000000091610falsefalsefalsefalsefalse2truefalsefalse9426900000094269falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets109false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse74falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Life insurance company general accounts [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 3 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Life_Insurance_Company_General_Accounts_Member_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Fair_Value_Inputs_Level3_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseLife insurance company general accounts [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_LifeInsuranceCompanyGeneralAccountsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥75falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Life insurance company general accounts [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 3 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Life_Insurance_Company_General_Accounts_Member_Fair_Value_Inputs_Level3_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseLife insurance company general accounts [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_LifeInsuranceCompanyGeneralAccountsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseJapanese plans [Member] | Life insurance company general accounts [Member] | Fair Value, Inputs, Level 3 [Member]110true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets111false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalse2truefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets112false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse76falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Other Assets [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Other_Assets_Member_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseOther Assets [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_OtherAssetsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥77falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Other Assets [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Other_Assets_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseOther Assets [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_OtherAssetsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseJapanese plans [Member] | Other Assets [Member]113true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets114false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse95600000009560falsefalsefalsefalsefalse2truefalsefalse91380000009138falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets115false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse78falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Other Assets [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 1 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Other_Assets_Member_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Fair_Value_Inputs_Level1_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseOther Assets [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_OtherAssetsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥79falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Other Assets [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 1 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Other_Assets_Member_Fair_Value_Inputs_Level1_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseOther Assets [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_OtherAssetsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseJapanese plans [Member] | Other Assets [Member] | Fair Value, Inputs, Level 1 [Member]116true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets117false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalse2truefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets118false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse80falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Other Assets [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 2 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Other_Assets_Member_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Fair_Value_Inputs_Level2_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseOther Assets [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_OtherAssetsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥81falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Other Assets [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 2 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Other_Assets_Member_Fair_Value_Inputs_Level2_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseOther Assets [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_OtherAssetsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseJapanese plans [Member] | Other Assets [Member] | Fair Value, Inputs, Level 2 [Member]119true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets120false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse85210000008521falsefalsefalsefalsefalse2truefalsefalse83670000008367falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets121false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse82falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Other Assets [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 3 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Other_Assets_Member_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Fair_Value_Inputs_Level3_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseOther Assets [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_OtherAssetsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥83falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Other Assets [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 3 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Other_Assets_Member_Fair_Value_Inputs_Level3_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseOther Assets [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_OtherAssetsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseJapanese plans [Member] | Other Assets [Member] | Fair Value, Inputs, Level 3 [Member]122true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets123false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse10390000001039falsefalsefalsefalsefalse2truefalsefalse771000000771falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets124false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse84falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 1 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Fair_Value_Inputs_Level1_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥85falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 1 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Fair_Value_Inputs_Level1_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseJapanese plans [Member] | Fair Value, Inputs, Level 1 [Member]125true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets126false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse6521600000065216falsefalsefalsefalsefalse2truefalsefalse6909100000069091falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets127false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse86falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 2 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Fair_Value_Inputs_Level2_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥87falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 2 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Fair_Value_Inputs_Level2_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseJapanese plans [Member] | Fair Value, Inputs, Level 2 [Member]128true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets129false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse393835000000393835falsefalsefalsefalsefalse2truefalsefalse387346000000387346falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets130false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse88falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 3 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Fair_Value_Inputs_Level3_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥89falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Japanese plans [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 3 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Domestic_Pension_Plans_Of_Foreign_Entity_Defined_Benefit_Member_Fair_Value_Inputs_Level3_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseJapanese plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DomesticPensionPlansOfForeignEntityDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseJapanese plans [Member] | Fair Value, Inputs, Level 3 [Member]131true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets132false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse10390000001039falsefalsefalsefalsefalse2truefalsefalse771000000771falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets133false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse90falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Foreign_Pension_Plans_Defined_Benefit_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170PureStandardhttp://www.xbrl.org/2003/instancepurexbrli0JPYJPY¥91falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Foreign_Pension_Plans_Defined_Benefit_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170PureStandardhttp://www.xbrl.org/2003/instancepurexbrli0JPYJPY¥92falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] 12/31/2008 JPY (¥) ¥BalanceAsOf_31Dec2008_Foreign_Pension_Plans_Defined_Benefit_Memberhttp://www.sec.gov/CIK0000016988instant2008-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseForeign plans [Member]134true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets135false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse197835000000197835falsefalsefalsefalsefalse2truefalsefalse7505800000075058falsefalsefalsefalsefalse3truefalsefalse6299600000062996falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets136false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse93falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Equity securites of Japanese Companies [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Equity_Securites_Of_Japanese_Companies_Member_Foreign_Pension_Plans_Defined_Benefit_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseEquity securites of Japanese Companies [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_EquitySecuritesOfJapaneseCompaniesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥94falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Equity securites of Japanese Companies [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Equity_Securites_Of_Japanese_Companies_Member_Foreign_Pension_Plans_Defined_Benefit_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseEquity securites of Japanese Companies [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_EquitySecuritesOfJapaneseCompaniesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseForeign plans [Member] | Equity securites of Japanese Companies [Member]137true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets138false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalse2truefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets139false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse95falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Equity securites of Japanese Companies [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 1 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Equity_Securites_Of_Japanese_Companies_Member_Foreign_Pension_Plans_Defined_Benefit_Member_Fair_Value_Inputs_Level1_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseEquity securites of Japanese Companies [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_EquitySecuritesOfJapaneseCompaniesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥96falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Equity securites of Japanese Companies [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 1 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Equity_Securites_Of_Japanese_Companies_Member_Foreign_Pension_Plans_Defined_Benefit_Member_Fair_Value_Inputs_Level1_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseEquity securites of Japanese Companies [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_EquitySecuritesOfJapaneseCompaniesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseForeign plans [Member] | Equity securites of Japanese Companies [Member] | Fair Value, Inputs, Level 1 [Member]140true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets141false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalse2truefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets142false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse97falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Equity securites of Japanese Companies [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 2 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Equity_Securites_Of_Japanese_Companies_Member_Foreign_Pension_Plans_Defined_Benefit_Member_Fair_Value_Inputs_Level2_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseEquity securites of Japanese Companies [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_EquitySecuritesOfJapaneseCompaniesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥98falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Equity securites of Japanese Companies [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 2 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Equity_Securites_Of_Japanese_Companies_Member_Foreign_Pension_Plans_Defined_Benefit_Member_Fair_Value_Inputs_Level2_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseEquity securites of Japanese Companies [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_EquitySecuritesOfJapaneseCompaniesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseForeign plans [Member] | Equity securites of Japanese Companies [Member] | Fair Value, Inputs, Level 2 [Member]143true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets144false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalse2truefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets145false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse99falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Equity securites of Japanese Companies [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 3 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Equity_Securites_Of_Japanese_Companies_Member_Foreign_Pension_Plans_Defined_Benefit_Member_Fair_Value_Inputs_Level3_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseEquity securites of Japanese Companies [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_EquitySecuritesOfJapaneseCompaniesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥100falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Equity securites of Japanese Companies [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 3 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Equity_Securites_Of_Japanese_Companies_Member_Foreign_Pension_Plans_Defined_Benefit_Member_Fair_Value_Inputs_Level3_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseEquity securites of Japanese Companies [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_EquitySecuritesOfJapaneseCompaniesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseForeign plans [Member] | Equity securites of Japanese Companies [Member] | Fair Value, Inputs, Level 3 [Member]146true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets147false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalse2truefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets148false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse101falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Equity Securites Of Foreign Companies [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Foreign_Pension_Plans_Defined_Benefit_Member_Equity_Securites_Of_Foreign_Companies_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseEquity Securites of Foreign Companies [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_EquitySecuritesOfForeignCompaniesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥102falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Equity Securites Of Foreign Companies [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Foreign_Pension_Plans_Defined_Benefit_Member_Equity_Securites_Of_Foreign_Companies_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseEquity Securites of Foreign Companies [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_EquitySecuritesOfForeignCompaniesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseForeign plans [Member] | Equity Securites of Foreign Companies [Member]149true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets150false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse34740000003474falsefalsefalsefalsefalse2truefalsefalse38980000003898falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets151false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse103falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Equity Securites Of Foreign Companies [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 1 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Foreign_Pension_Plans_Defined_Benefit_Member_Fair_Value_Inputs_Level1_Member_Equity_Securites_Of_Foreign_Companies_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseEquity Securites of Foreign Companies [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_EquitySecuritesOfForeignCompaniesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥104falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Equity Securites Of Foreign Companies [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 1 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Foreign_Pension_Plans_Defined_Benefit_Member_Fair_Value_Inputs_Level1_Member_Equity_Securites_Of_Foreign_Companies_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseEquity Securites of Foreign Companies [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_EquitySecuritesOfForeignCompaniesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseForeign plans [Member] | Equity Securites of Foreign Companies [Member] | Fair Value, Inputs, Level 1 [Member]152true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets153false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse34740000003474falsefalsefalsefalsefalse2truefalsefalse38980000003898falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets154false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse105falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Equity Securites Of Foreign Companies [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 2 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Foreign_Pension_Plans_Defined_Benefit_Member_Fair_Value_Inputs_Level2_Member_Equity_Securites_Of_Foreign_Companies_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseEquity Securites of Foreign Companies [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_EquitySecuritesOfForeignCompaniesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥106falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Equity Securites Of Foreign Companies [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 2 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Foreign_Pension_Plans_Defined_Benefit_Member_Fair_Value_Inputs_Level2_Member_Equity_Securites_Of_Foreign_Companies_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseEquity Securites of Foreign Companies [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_EquitySecuritesOfForeignCompaniesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseForeign plans [Member] | Equity Securites of Foreign Companies [Member] | Fair Value, Inputs, Level 2 [Member]155true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets156false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalse2truefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets157false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse107falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Equity Securites Of Foreign Companies [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 3 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Foreign_Pension_Plans_Defined_Benefit_Member_Fair_Value_Inputs_Level3_Member_Equity_Securites_Of_Foreign_Companies_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseEquity Securites of Foreign Companies [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_EquitySecuritesOfForeignCompaniesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥108falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Equity Securites Of Foreign Companies [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 3 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Foreign_Pension_Plans_Defined_Benefit_Member_Fair_Value_Inputs_Level3_Member_Equity_Securites_Of_Foreign_Companies_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseEquity Securites of Foreign Companies [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_EquitySecuritesOfForeignCompaniesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseForeign plans [Member] | Equity Securites of Foreign Companies [Member] | Fair Value, Inputs, Level 3 [Member]158true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets159false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalse2truefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets160false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse109falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Pooled Equity Funds [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Pooled_Equity_Funds_Member_Foreign_Pension_Plans_Defined_Benefit_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalsePooled Equity Funds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_PooledEquityFundsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥110falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Pooled Equity Funds [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Foreign_Pension_Plans_Defined_Benefit_Member_Pooled_Equity_Funds_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalsePooled Equity Funds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_PooledEquityFundsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseForeign plans [Member] | Pooled Equity Funds [Member]161true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets162false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse8066600000080666falsefalsefalsefalsefalse2truefalsefalse4729000000047290falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets163false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse111falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Pooled Equity Funds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 1 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Pooled_Equity_Funds_Member_Foreign_Pension_Plans_Defined_Benefit_Member_Fair_Value_Inputs_Level1_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalsePooled Equity Funds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_PooledEquityFundsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥112falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Pooled Equity Funds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 1 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Foreign_Pension_Plans_Defined_Benefit_Member_Pooled_Equity_Funds_Member_Fair_Value_Inputs_Level1_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalsePooled Equity Funds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_PooledEquityFundsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseForeign plans [Member] | Pooled Equity Funds [Member] | Fair Value, Inputs, Level 1 [Member]164true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets165false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalse2truefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets166false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse113falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Pooled Equity Funds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 2 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Pooled_Equity_Funds_Member_Foreign_Pension_Plans_Defined_Benefit_Member_Fair_Value_Inputs_Level2_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalsePooled Equity Funds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_PooledEquityFundsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥114falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Pooled Equity Funds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 2 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Foreign_Pension_Plans_Defined_Benefit_Member_Pooled_Equity_Funds_Member_Fair_Value_Inputs_Level2_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalsePooled Equity Funds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_PooledEquityFundsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseForeign plans [Member] | Pooled Equity Funds [Member] | Fair Value, Inputs, Level 2 [Member]167true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets168false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse8066600000080666falsefalsefalsefalsefalse2truefalsefalse4729000000047290falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets169false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse115falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Pooled Equity Funds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 3 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Pooled_Equity_Funds_Member_Foreign_Pension_Plans_Defined_Benefit_Member_Fair_Value_Inputs_Level3_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalsePooled Equity Funds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_PooledEquityFundsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥116falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Pooled Equity Funds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 3 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Foreign_Pension_Plans_Defined_Benefit_Member_Pooled_Equity_Funds_Member_Fair_Value_Inputs_Level3_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalsePooled Equity Funds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_PooledEquityFundsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseForeign plans [Member] | Pooled Equity Funds [Member] | Fair Value, Inputs, Level 3 [Member]170true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets171false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalse2truefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets172false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse117falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Government Bonds [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_U_S_Government_Agencies_Debt_Securities_Member_Foreign_Pension_Plans_Defined_Benefit_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseGovernment Bonds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_USGovernmentAgenciesDebtSecuritiesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥118falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Government Bonds [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Foreign_Pension_Plans_Defined_Benefit_Member_U_S_Government_Agencies_Debt_Securities_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseGovernment Bonds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_USGovernmentAgenciesDebtSecuritiesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseForeign plans [Member] | Government Bonds [Member]173true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets174false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse20740000002074falsefalsefalsefalsefalse2truefalsefalse15810000001581falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets175false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse119falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Government Bonds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 1 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_U_S_Government_Agencies_Debt_Securities_Member_Foreign_Pension_Plans_Defined_Benefit_Member_Fair_Value_Inputs_Level1_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseGovernment Bonds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_USGovernmentAgenciesDebtSecuritiesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥120falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Government Bonds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 1 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Foreign_Pension_Plans_Defined_Benefit_Member_U_S_Government_Agencies_Debt_Securities_Member_Fair_Value_Inputs_Level1_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseGovernment Bonds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_USGovernmentAgenciesDebtSecuritiesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseForeign plans [Member] | Government Bonds [Member] | Fair Value, Inputs, Level 1 [Member]176true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets177false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse20740000002074falsefalsefalsefalsefalse2truefalsefalse15810000001581falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets178false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse121falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Government Bonds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 2 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_U_S_Government_Agencies_Debt_Securities_Member_Foreign_Pension_Plans_Defined_Benefit_Member_Fair_Value_Inputs_Level2_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseGovernment Bonds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_USGovernmentAgenciesDebtSecuritiesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥122falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Government Bonds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 2 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Foreign_Pension_Plans_Defined_Benefit_Member_U_S_Government_Agencies_Debt_Securities_Member_Fair_Value_Inputs_Level2_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseGovernment Bonds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_USGovernmentAgenciesDebtSecuritiesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseForeign plans [Member] | Government Bonds [Member] | Fair Value, Inputs, Level 2 [Member]179true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets180false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalse2truefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets181false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse123falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Government Bonds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 3 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_U_S_Government_Agencies_Debt_Securities_Member_Foreign_Pension_Plans_Defined_Benefit_Member_Fair_Value_Inputs_Level3_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseGovernment Bonds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_USGovernmentAgenciesDebtSecuritiesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥124falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Government Bonds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 3 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Foreign_Pension_Plans_Defined_Benefit_Member_U_S_Government_Agencies_Debt_Securities_Member_Fair_Value_Inputs_Level3_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseGovernment Bonds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_USGovernmentAgenciesDebtSecuritiesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseForeign plans [Member] | Government Bonds [Member] | Fair Value, Inputs, Level 3 [Member]182true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets183false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalse2truefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets184false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse125falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Municipal Bonds [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Municipal_Bonds_Member_Foreign_Pension_Plans_Defined_Benefit_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseMunicipal Bonds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MunicipalBondsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥126falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Municipal Bonds [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Foreign_Pension_Plans_Defined_Benefit_Member_Municipal_Bonds_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseMunicipal Bonds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MunicipalBondsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseForeign plans [Member] | Municipal Bonds [Member]185true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets186false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalse2truefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets187false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse127falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Municipal Bonds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 1 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Municipal_Bonds_Member_Foreign_Pension_Plans_Defined_Benefit_Member_Fair_Value_Inputs_Level1_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseMunicipal Bonds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MunicipalBondsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥128falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Municipal Bonds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 1 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Foreign_Pension_Plans_Defined_Benefit_Member_Municipal_Bonds_Member_Fair_Value_Inputs_Level1_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseMunicipal Bonds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MunicipalBondsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseForeign plans [Member] | Municipal Bonds [Member] | Fair Value, Inputs, Level 1 [Member]188true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets189false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalse2truefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets190false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse129falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Municipal Bonds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 2 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Municipal_Bonds_Member_Foreign_Pension_Plans_Defined_Benefit_Member_Fair_Value_Inputs_Level2_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseMunicipal Bonds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MunicipalBondsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥130falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Municipal Bonds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 2 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Foreign_Pension_Plans_Defined_Benefit_Member_Municipal_Bonds_Member_Fair_Value_Inputs_Level2_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseMunicipal Bonds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MunicipalBondsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseForeign plans [Member] | Municipal Bonds [Member] | Fair Value, Inputs, Level 2 [Member]191true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets192false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalse2truefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets193false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse131falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Municipal Bonds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 3 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Municipal_Bonds_Member_Foreign_Pension_Plans_Defined_Benefit_Member_Fair_Value_Inputs_Level3_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseMunicipal Bonds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MunicipalBondsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥132falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Municipal Bonds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 3 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Foreign_Pension_Plans_Defined_Benefit_Member_Municipal_Bonds_Member_Fair_Value_Inputs_Level3_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseMunicipal Bonds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MunicipalBondsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseForeign plans [Member] | Municipal Bonds [Member] | Fair Value, Inputs, Level 3 [Member]194true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets195false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalse2truefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets196false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse133falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Corporate Bonds [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Corporate_Bond_Securities_Member_Foreign_Pension_Plans_Defined_Benefit_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseCorporate Bonds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CorporateBondSecuritiesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥134falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Corporate Bonds [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Foreign_Pension_Plans_Defined_Benefit_Member_Corporate_Bond_Securities_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseCorporate Bonds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CorporateBondSecuritiesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseForeign plans [Member] | Corporate Bonds [Member]197true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets198false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalse2truefalsefalse66730000006673falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets199false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse135falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Corporate Bonds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 1 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Corporate_Bond_Securities_Member_Foreign_Pension_Plans_Defined_Benefit_Member_Fair_Value_Inputs_Level1_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseCorporate Bonds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CorporateBondSecuritiesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥136falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Corporate Bonds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 1 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Foreign_Pension_Plans_Defined_Benefit_Member_Corporate_Bond_Securities_Member_Fair_Value_Inputs_Level1_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseCorporate Bonds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CorporateBondSecuritiesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseForeign plans [Member] | Corporate Bonds [Member] | Fair Value, Inputs, Level 1 [Member]200true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets201false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalse2truefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets202false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse137falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Corporate Bonds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 2 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Corporate_Bond_Securities_Member_Foreign_Pension_Plans_Defined_Benefit_Member_Fair_Value_Inputs_Level2_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseCorporate Bonds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CorporateBondSecuritiesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥138falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Corporate Bonds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 2 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Foreign_Pension_Plans_Defined_Benefit_Member_Corporate_Bond_Securities_Member_Fair_Value_Inputs_Level2_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseCorporate Bonds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CorporateBondSecuritiesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseForeign plans [Member] | Corporate Bonds [Member] | Fair Value, Inputs, Level 2 [Member]203true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets204false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalse2truefalsefalse66730000006673falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets205false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse139falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Corporate Bonds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 3 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Corporate_Bond_Securities_Member_Foreign_Pension_Plans_Defined_Benefit_Member_Fair_Value_Inputs_Level3_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseCorporate Bonds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CorporateBondSecuritiesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥140falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Corporate Bonds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 3 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Foreign_Pension_Plans_Defined_Benefit_Member_Corporate_Bond_Securities_Member_Fair_Value_Inputs_Level3_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseCorporate Bonds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CorporateBondSecuritiesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseForeign plans [Member] | Corporate Bonds [Member] | Fair Value, Inputs, Level 3 [Member]206true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets207false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalse2truefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets208false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse141falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Pooled Debt Funds [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Pooled_Debt_Funds_Member_Foreign_Pension_Plans_Defined_Benefit_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalsePooled Debt Funds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_PooledDebtFundsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥142falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Pooled Debt Funds [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Foreign_Pension_Plans_Defined_Benefit_Member_Pooled_Debt_Funds_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalsePooled Debt Funds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_PooledDebtFundsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseForeign plans [Member] | Pooled Debt Funds [Member]209true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets210false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse104650000000104650falsefalsefalsefalsefalse2truefalsefalse93430000009343falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets211false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse143falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Pooled Debt Funds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 1 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Pooled_Debt_Funds_Member_Foreign_Pension_Plans_Defined_Benefit_Member_Fair_Value_Inputs_Level1_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalsePooled Debt Funds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_PooledDebtFundsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥144falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Pooled Debt Funds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 1 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Foreign_Pension_Plans_Defined_Benefit_Member_Pooled_Debt_Funds_Member_Fair_Value_Inputs_Level1_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalsePooled Debt Funds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_PooledDebtFundsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseForeign plans [Member] | Pooled Debt Funds [Member] | Fair Value, Inputs, Level 1 [Member]212true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets213false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalse2truefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets214false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse145falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Pooled Debt Funds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 2 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Pooled_Debt_Funds_Member_Foreign_Pension_Plans_Defined_Benefit_Member_Fair_Value_Inputs_Level2_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalsePooled Debt Funds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_PooledDebtFundsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥146falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Pooled Debt Funds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 2 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Foreign_Pension_Plans_Defined_Benefit_Member_Pooled_Debt_Funds_Member_Fair_Value_Inputs_Level2_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalsePooled Debt Funds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_PooledDebtFundsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseForeign plans [Member] | Pooled Debt Funds [Member] | Fair Value, Inputs, Level 2 [Member]215true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets216false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse104650000000104650falsefalsefalsefalsefalse2truefalsefalse93430000009343falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets217false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse147falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Pooled Debt Funds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 3 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Pooled_Debt_Funds_Member_Foreign_Pension_Plans_Defined_Benefit_Member_Fair_Value_Inputs_Level3_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalsePooled Debt Funds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_PooledDebtFundsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥148falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Pooled Debt Funds [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 3 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Foreign_Pension_Plans_Defined_Benefit_Member_Pooled_Debt_Funds_Member_Fair_Value_Inputs_Level3_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalsePooled Debt Funds [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_PooledDebtFundsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseForeign plans [Member] | Pooled Debt Funds [Member] | Fair Value, Inputs, Level 3 [Member]218true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets219false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalse2truefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets220false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse149falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Mortgage Backed Securities and other asset backed securities [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Mortgage_Backed_Securities_And_Other_Asset_Backed_Securities_Member_Foreign_Pension_Plans_Defined_Benefit_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseMotgage backed securities (and other asset backed securities)us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_MortgageBackedSecuritiesAndOtherAssetBackedSecuritiesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥150falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Mortgage Backed Securities and other asset backed securities [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Foreign_Pension_Plans_Defined_Benefit_Member_Mortgage_Backed_Securities_And_Other_Asset_Backed_Securities_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseMotgage backed securities (and other asset backed securities)us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_MortgageBackedSecuritiesAndOtherAssetBackedSecuritiesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseForeign plans [Member] | Motgage backed securities (and other asset backed securities)221true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets222false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse232000000232falsefalsefalsefalsefalse2truefalsefalse256000000256falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets223false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse151falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Mortgage Backed Securities and other asset backed securities [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 1 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Mortgage_Backed_Securities_And_Other_Asset_Backed_Securities_Member_Foreign_Pension_Plans_Defined_Benefit_Member_Fair_Value_Inputs_Level1_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseMotgage backed securities (and other asset backed securities)us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_MortgageBackedSecuritiesAndOtherAssetBackedSecuritiesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥152falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Mortgage Backed Securities and other asset backed securities [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 1 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Foreign_Pension_Plans_Defined_Benefit_Member_Mortgage_Backed_Securities_And_Other_Asset_Backed_Securities_Member_Fair_Value_Inputs_Level1_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseMotgage backed securities (and other asset backed securities)us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_MortgageBackedSecuritiesAndOtherAssetBackedSecuritiesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseForeign plans [Member] | Motgage backed securities (and other asset backed securities) | Fair Value, Inputs, Level 1 [Member]224true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets225false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalse2truefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets226false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse153falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Mortgage Backed Securities and other asset backed securities [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 2 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Mortgage_Backed_Securities_And_Other_Asset_Backed_Securities_Member_Foreign_Pension_Plans_Defined_Benefit_Member_Fair_Value_Inputs_Level2_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseMotgage backed securities (and other asset backed securities)us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_MortgageBackedSecuritiesAndOtherAssetBackedSecuritiesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥154falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Mortgage Backed Securities and other asset backed securities [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 2 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Foreign_Pension_Plans_Defined_Benefit_Member_Mortgage_Backed_Securities_And_Other_Asset_Backed_Securities_Member_Fair_Value_Inputs_Level2_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseMotgage backed securities (and other asset backed securities)us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_MortgageBackedSecuritiesAndOtherAssetBackedSecuritiesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseForeign plans [Member] | Motgage backed securities (and other asset backed securities) | Fair Value, Inputs, Level 2 [Member]227true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets228false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse232000000232falsefalsefalsefalsefalse2truefalsefalse256000000256falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets229false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse155falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Mortgage Backed Securities and other asset backed securities [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 3 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Mortgage_Backed_Securities_And_Other_Asset_Backed_Securities_Member_Foreign_Pension_Plans_Defined_Benefit_Member_Fair_Value_Inputs_Level3_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseMotgage backed securities (and other asset backed securities)us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_MortgageBackedSecuritiesAndOtherAssetBackedSecuritiesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥156falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Mortgage Backed Securities and other asset backed securities [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 3 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Foreign_Pension_Plans_Defined_Benefit_Member_Mortgage_Backed_Securities_And_Other_Asset_Backed_Securities_Member_Fair_Value_Inputs_Level3_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseMotgage backed securities (and other asset backed securities)us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_MortgageBackedSecuritiesAndOtherAssetBackedSecuritiesMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseForeign plans [Member] | Motgage backed securities (and other asset backed securities) | Fair Value, Inputs, Level 3 [Member]230true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets231false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalse2truefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets232false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse157falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Life insurance company general accounts [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Life_Insurance_Company_General_Accounts_Member_Foreign_Pension_Plans_Defined_Benefit_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseLife insurance company general accounts [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_LifeInsuranceCompanyGeneralAccountsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥158falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Life insurance company general accounts [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Foreign_Pension_Plans_Defined_Benefit_Member_Life_Insurance_Company_General_Accounts_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseLife insurance company general accounts [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_LifeInsuranceCompanyGeneralAccountsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseForeign plans [Member] | Life insurance company general accounts [Member]233true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets234false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalse2truefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets235false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse159falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Life insurance company general accounts [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 1 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Life_Insurance_Company_General_Accounts_Member_Foreign_Pension_Plans_Defined_Benefit_Member_Fair_Value_Inputs_Level1_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseLife insurance company general accounts [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_LifeInsuranceCompanyGeneralAccountsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥160falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Life insurance company general accounts [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 1 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Foreign_Pension_Plans_Defined_Benefit_Member_Life_Insurance_Company_General_Accounts_Member_Fair_Value_Inputs_Level1_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseLife insurance company general accounts [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_LifeInsuranceCompanyGeneralAccountsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseForeign plans [Member] | Life insurance company general accounts [Member] | Fair Value, Inputs, Level 1 [Member]236true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets237false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalse2truefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets238false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse161falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Life insurance company general accounts [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 2 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Life_Insurance_Company_General_Accounts_Member_Foreign_Pension_Plans_Defined_Benefit_Member_Fair_Value_Inputs_Level2_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseLife insurance company general accounts [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_LifeInsuranceCompanyGeneralAccountsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥162falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Life insurance company general accounts [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 2 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Foreign_Pension_Plans_Defined_Benefit_Member_Life_Insurance_Company_General_Accounts_Member_Fair_Value_Inputs_Level2_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseLife insurance company general accounts [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_LifeInsuranceCompanyGeneralAccountsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseForeign plans [Member] | Life insurance company general accounts [Member] | Fair Value, Inputs, Level 2 [Member]239true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets240false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalse2truefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets241false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse163falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Life insurance company general accounts [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 3 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Life_Insurance_Company_General_Accounts_Member_Foreign_Pension_Plans_Defined_Benefit_Member_Fair_Value_Inputs_Level3_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseLife insurance company general accounts [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_LifeInsuranceCompanyGeneralAccountsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥164falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Life insurance company general accounts [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 3 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Foreign_Pension_Plans_Defined_Benefit_Member_Life_Insurance_Company_General_Accounts_Member_Fair_Value_Inputs_Level3_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseLife insurance company general accounts [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldicaj_LifeInsuranceCompanyGeneralAccountsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseForeign plans [Member] | Life insurance company general accounts [Member] | Fair Value, Inputs, Level 3 [Member]242true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets243false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalse2truefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets244false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse165falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Other Assets [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Other_Assets_Member_Foreign_Pension_Plans_Defined_Benefit_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseOther Assets [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_OtherAssetsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥166falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Other Assets [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Foreign_Pension_Plans_Defined_Benefit_Member_Other_Assets_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseOther Assets [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_OtherAssetsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseForeign plans [Member] | Other Assets [Member]245true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets246false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse67390000006739falsefalsefalsefalsefalse2truefalsefalse60170000006017falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets247false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse167falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Other Assets [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 1 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Other_Assets_Member_Foreign_Pension_Plans_Defined_Benefit_Member_Fair_Value_Inputs_Level1_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseOther Assets [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_OtherAssetsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥168falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Other Assets [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 1 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Foreign_Pension_Plans_Defined_Benefit_Member_Other_Assets_Member_Fair_Value_Inputs_Level1_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseOther Assets [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_OtherAssetsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseForeign plans [Member] | Other Assets [Member] | Fair Value, Inputs, Level 1 [Member]248true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets249false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalse2truefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets250false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse169falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Other Assets [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 2 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Other_Assets_Member_Foreign_Pension_Plans_Defined_Benefit_Member_Fair_Value_Inputs_Level2_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseOther Assets [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_OtherAssetsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥170falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Other Assets [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 2 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Foreign_Pension_Plans_Defined_Benefit_Member_Other_Assets_Member_Fair_Value_Inputs_Level2_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseOther Assets [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_OtherAssetsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseForeign plans [Member] | Other Assets [Member] | Fair Value, Inputs, Level 2 [Member]251true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets252false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse67390000006739falsefalsefalsefalsefalse2truefalsefalse60170000006017falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets253false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse171falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Other Assets [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 3 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Other_Assets_Member_Foreign_Pension_Plans_Defined_Benefit_Member_Fair_Value_Inputs_Level3_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseOther Assets [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_OtherAssetsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥172falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Other Assets [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 3 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Foreign_Pension_Plans_Defined_Benefit_Member_Other_Assets_Member_Fair_Value_Inputs_Level3_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseOther Assets [Member]us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_OtherAssetsMemberus-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseForeign plans [Member] | Other Assets [Member] | Fair Value, Inputs, Level 3 [Member]254true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets255false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalse2truefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets256false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse173falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 1 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Foreign_Pension_Plans_Defined_Benefit_Member_Fair_Value_Inputs_Level1_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥174falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 1 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Foreign_Pension_Plans_Defined_Benefit_Member_Fair_Value_Inputs_Level1_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseFair Value, Inputs, Level 1 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel1Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseForeign plans [Member] | Fair Value, Inputs, Level 1 [Member]257true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets258false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse55480000005548falsefalsefalsefalsefalse2truefalsefalse54790000005479falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets259false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse175falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 2 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Foreign_Pension_Plans_Defined_Benefit_Member_Fair_Value_Inputs_Level2_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥176falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 2 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Foreign_Pension_Plans_Defined_Benefit_Member_Fair_Value_Inputs_Level2_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseFair Value, Inputs, Level 2 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel2Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseForeign plans [Member] | Fair Value, Inputs, Level 2 [Member]260true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets261false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse192287000000192287falsefalsefalsefalsefalse2truefalsefalse6957900000069579falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets262false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse177falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 3 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Foreign_Pension_Plans_Defined_Benefit_Member_Fair_Value_Inputs_Level3_Memberhttp://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥178falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Foreign plans [Member] {us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 3 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Foreign_Pension_Plans_Defined_Benefit_Member_Fair_Value_Inputs_Level3_Memberhttp://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseForeign plans [Member]us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ForeignPensionPlansDefinedBenefitMemberus-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxisexplicitMemberfalsefalseFair Value, Inputs, Level 3 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseForeign plans [Member] | Fair Value, Inputs, Level 3 [Member]263true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets264false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalse2truefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets265false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://canon.com/role/employeeretirementandseverancebenefitsdetails41falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse179falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 3 [Member] 12/31/2010 JPY (¥) ¥BalanceAsOf_31Dec2010_Fair_Value_Inputs_Level3_Member_3http://www.sec.gov/CIK0000016988instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseFair Value, Inputs, Level 3 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥180falsefalseJPYtruefalse{us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxis} : Fair Value, Inputs, Level 3 [Member] 12/31/2009 JPY (¥) ¥BalanceAsOf_31Dec2009_Fair_Value_Inputs_Level3_Member_3http://www.sec.gov/CIK0000016988instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseFair Value, Inputs, Level 3 [Member]us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_DefinedBenefitPlanFairValueOfPlanAssetsByMeasurementAxisexplicitMemberJPYStandardhttp://www.xbrl.org/2003/iso4217JPYiso42170JPYJPY¥OthernaNo definition available.No authoritative reference available.falsefalseFair Value, Inputs, Level 3 [Member]266true0us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseFair values of Company's Pension Plans assets267false0us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse10390000001039falsetruefalsefalsefalse2truefalsefalse771000000771falsetruefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAssets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 falsefalseFair values of Company's pension plans assets3267Employee Retirement and Severance Benefits (Details 5) (JPY ¥)MillionsUnKnownUnKnownUnKnownfalsetrue