Accounts Notes And Loans Receivable [Line Items] Accounts, Notes, Loans and Financing Receivable [Line Items] Accounts Notes And Loans Receivable Net Current Trade receivables, net (Note 3) Trade receivables, net (Note 3) Accounts Payable And Accrued Liabilities Disclosure [Text Block] Trade Payables Accounts Payable and Accrued Liabilities [Line Items] Accounts Payable And Accrued Liabilities [Line Items] Accounts Payable and Accrued Liabilities [Line Items] Accounts Payable and Accrued Liabilities [Table] Accounts Payable And Accrued Liabilities [Table] Accounts Payable and Accrued Liabilities [Table] Accounts Payable Trade Current Accounts Accounts Receivable Gross Current Accounts Accrued Income Taxes Current Accrued income taxes (Note 12) Accrued Liabilities Current Accrued expenses (Notes 11 and 18) Accumulated Depreciation Depletion And Amortization Property Plant And Equipment Less accumulated depreciation Accumulated Other Comprehensive Income, Adjustment Total Accumulated Other Comprehensive Income Adjustment Total Adjustments for the year Accumulated Other Comprehensive Income Defined Benefit Plans Adjustment, Net of Tax Period Increase Decrease [Abstract] Accumulated Other Comprehensive Income Defined Benefit Plans Adjustment Net Of Tax Period Increase Decrease [Abstract] Pension liability adjustments: Accumulated Other Comprehensive Income, Derivative Instrument, Adjustment for the Year Accumulated Other Comprehensive Income Derivative Instrument Adjustment For The Year Adjustments for the year Accumulated Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax Balance at end of year Balance at beginning of year Accumulated Other Comprehensive Income (Loss), Available-For-Sale Securities Adjustment, Net of Tax [Abstract] Accumulated Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax [Abstract] Net unrealized gains and losses on securities: Accumulated Other Comprehensive Income Loss Defined Benefit Pension And Other Postretirement Plans Net Of Tax Balance at end of year Balance at beginning of year Accumulated Other Comprehensive Income Loss Derivative Instrument Adjustment, Net Of Tax [Abstract] Accumulated Other Comprehensive Income Loss Derivative Instrument Adjustment Net Of Tax [Abstract] Net gains and losses on derivative instruments: Accumulated Other Comprehensive Income (Loss), Derivative Instrument, Net of Tax Accumulated Other Comprehensive Income Loss Derivative Instrument Net Of Tax Balance at end of year Balance at beginning of year Accumulated Other Comprehensive Income Loss Foreign Currency Translation Adjustment Net Of Tax Balance at end of year Balance at beginning of year Accumulated Other Comprehensive Income (Loss) [Line Items] Accumulated Other Comprehensive Income Loss [Line Items] Accumulated Other Comprehensive Income (Loss) [Line Items] Accumulated Other Comprehensive Income Loss Net Of Tax Balance at end of year Balance at beginning of year Accumulated other comprehensive income (loss) (Note 14) Accumulated Other Comprehensive Income Loss Net Of Tax [Abstract] Total accumulated other comprehensive income (loss): Accumulated Other Comprehensive Income (Loss) [Table] Accumulated Other Comprehensive Income Loss [Table] Accumulated Other Comprehensive Income (Loss) [Table] Accumulated Other Comprehensive Income [Member] Accumulated other comprehensive income (loss) Accumulated Other Comprehensive Income, Pension Liability Adjustment Accumulated Other Comprehensive Income Pension Liability Adjustment Adjustments for the year Accumulated Translation Adjustment [Member] Accumulated Translation Adjustment Acquired Finite Lived Intangible Asset Amount Intangible assets developed or acquired Acquired Finite Lived Intangible Assets By Major Class [Axis] Acquired Finite-Lived Intangible Assets by Major Class [Axis] Acquired Finite Lived Intangible Asset Weighted Average Useful Life Weighted average amortization period for acquired intangible assets Additional Acquisition Shares Representing Certain Percentage of Total Outstanding Shares of Acquiree Additional Acquisition Shares Representing Certain Percentage Of Total Outstanding Shares Of Acquiree Additional acquisition shares representing certain percentage of total outstanding shares of Acquiree Additional Paid In Capital Common Stock Additional paid-in capital Additional Paid In Capital [Member] Additional paid-in capital Adjustments To Reconcile Net Income Loss To Cash Provided By Used In Operating Activities [Abstract] Adjustments to reconcile consolidated net income to net cash provided by operating activities: Advertising Costs Policy [Text Block] Advertising Costs Advertising Expense Advertising expenses Affiliates and Other Companies [Member] Affiliates And Other Companies [Member] Affiliates and Other Companies Allocated Share Based Compensation Expense Recognized compensation cost for stock options Allowance For Credit Losses On Financing Receivables Table [Text Block] Allowance for Credit Losses A valuation allowance for trade notes and accounts receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible. Allowance For Doubtful Trade Notes And Accounts Receivable Current Less allowance for doubtful receivables Allowance For Losses On Finance Receivables [Member] Finance Receivables Allowance For Trade Receivables [Member] Trade Receivables Amendment Flag Amendment Flag Americas [Member] Americas [Member] Americas Amount Available For Dividend Distribution With Approval From Regulatory Agencies Amount available for dividends under the Corporation Law of Japan Amount Due for Purchase of Property Plant and Equipment Amount Due For Purchase Of Property Plant And Equipment Amount due for purchase of property, plant and equipment Amount Paid Additional to Acquisition of Outstanding Shares of Subsidiary Amount Paid Additional To Acquisition Of Outstanding Shares Of Subsidiary Amount paid additional to acquisition of outstanding shares of subsidiary Appropriations Not Required if Percentage of Additional Paid in Capital and Legal Reserve Equals Specific Percentage of Respective Stated Capital Appropriations Not Required If Percentage Of Additional Paid In Capital And Legal Reserve Equals Specific Percentage Of Respective Stated Capital Appropriations not required if percentage of additional paid in capital and legal reserve equals specific percentage of respective stated capital Asia and Oceania [Member] Asia And Oceania [Member] Asia and Oceania Assets Total assets Total assets Assets [Abstract] Assets Assets Current Total current assets Assets Current [Abstract] Current assets: Assets Fair Value Disclosure [Abstract] Assets: Assets Fair Value Disclosure Recurring Total assets Assets Leased To Others [Member] Assets Leased to Others Available For Sale Securities Amortized Cost Cost Available For Sale Securities Change In Net Unrealized Holding Gain Loss Adjustments for the year Available For Sale Securities Current Available-for-sale (current) Available for sale Securities Current [Member] Available For Sale Securities Current [Member] Available for sale Securities Current Available For Sale Securities Debt Maturities After Five Through Ten Years Amortized Cost Due after five years through ten years Available For Sale Securities Debt Maturities After Five Through Ten Years Fair Value Due after five years through ten years Available For Sale Securities Debt Maturities After One Through Five Years Amortized Cost Due after one year through five years Available For Sale Securities Debt Maturities After One Through Five Years Fair Value Due after one year through five years Available For Sale Securities Debt Maturities Amortized Cost Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Total Available For Sale Securities Debt Maturities Amortized Cost [Abstract] Cost Available For Sale Securities Debt Maturities Fair Value [Abstract] Fair value Available For Sale Securities Debt Maturities Within One Year Amortized Cost Due within one year Available For Sale Securities Debt Maturities Within One Year Fair Value Due within one year Available For Sale Securities Debt Securities Available-for-sale Securities, Debt Securities, Total Available For Sale Securities Fair Value Disclosure Fair value Available For Sale Securities Gross Realized Gains Gross realized gains Available For Sale Securities Gross Realized Losses Gross realized losses Availableforsale Securities Gross Unrealized Gain Gross unrealized holding gains Available For Sale Securities Gross Unrealized Losses 1 Gross unrealized holding losses Availableforsale Securities [Member] Available-for-sale Securities Available For Sale Securities Noncurrent Available-for-sale (noncurrent) Available for sale Securities Non Current [Member] Available For Sale Securities Non Current [Member] Available for sale Securities Noncurrent Balance Sheet Location [Domain] Balance Sheet Location [Domain] Basis of Presentation Basis Of Presentation Policy [Text Block] Basis of Presentation Building [Member] Building Buildings And Improvements Gross Buildings Business Acquisition Acquiree [Domain] Business Acquisition, Acquiree [Domain] Business Acquisition [Axis] Business Acquisition [Axis] Business Acquisition Cost Of Acquired Entity Cash Paid Consideration for principally a fully self-funded public cash tender offer Business Acquisition [Line Items] Business Acquisition [Line Items] Business Acquisition Percentage Of Voting Interests Acquired Acquisition of total outstanding shares Business Acquisition Purchase Price Allocation Amortizable Intangible Assets Intangible assets Intangible assets acquired, subject to amortization Business Acquisition Purchase Price Allocation Assets Acquired Total acquired assets Business Acquisition Purchase Price Allocation Assets Acquired Liabilities Assumed Net Net assets acquired Business Acquisition Purchase Price Allocation Current Assets Current assets Business Acquisition Purchase Price Allocation Goodwill Amount Goodwill Business Acquisition Purchase Price Allocation Liabilities Assumed Total assumed liabilities Business Acquisition Purchase Price Allocation Noncurrent Assets Non-current assets Business Acquisition Purchase Price Allocation Other Noncurrent Assets Other noncurrent assets Business Acquisition Purchase Price Allocation Property Plant And Equipment Property, plant and equipment Business Acquisitions Pro Forma Revenue Unaudited pro forma net sales of Oce included in the parent company's consolidated statement of income Business Combination Acquisition Of Less Than 100 Percent Noncontrolling Interest Fair Value Fair value of noncontrolling interest Business Combination Disclosure [Text Block] Acquisitions Business Combination Pro Forma Information Revenue Of Acquiree Since Acquisition Date Actual Amounts of net sales of Oce included in the parent company's consolidated statement of income Business Combination Step Acquisition Equity Interest In Acquiree Fair Value Acquisition-date fair value of the previous equity interest Business Combination Step Acquisition Equity Interest In Acquiree Percentage Interest held before the public cash tender offer Business Intersegment Eliminations [Member] Corporate and eliminations Business Segment [Member] Business Segment [Member] Business Segment Canon Finetech Inc, Canon Machinery Inc and Tokki Corporation [Member] Canon Finetech Inc Canon Machinery Inc And Tokki Corporation [Member] Canon Finetech Inc, Canon Machinery Inc and Tokki Corporation Capital Additions [Member] Purchase of Property, Plant and Equipment Capital Lease Obligations Capital lease obligations Capital Leases Future Minimum Payments Receivable Total minimum lease payments receivable Total minimum lease payments receivable Capital Leases Future Minimum Payments Receivable [Abstract] Financing leases Capital Leases Future Minimum Payments Receivable Current 2012 Capital Leases Future Minimum Payments Receivable Due Thereafter Thereafter Capital Leases Future Minimum Payments Receivable In Five Years 2016 Capital Leases Future Minimum Payments Receivable In Four Years 2015 Capital Leases Future Minimum Payments Receivable In Three Years 2014 Capital Leases Future Minimum Payments Receivable In Two Years 2013 Capital Leases Lessor Balance Sheet Net Investment In Direct Financing And Sales Type Leases Current Less current portion Capital Leases Lessor Balance Sheet Net Investment In Direct Financing And Sales Type Leases Noncurrent Capital Leases, Lessor Balance Sheet, Net Investment in Direct Financing and Sales Type Leases, Noncurrent, Total Capital Leases Net Investment In Direct Financing And Sales Type Leases Capital Leases, Net Investment in Direct Financing and Sales Type Leases, Total Capital Leases, Net Investment in Sales Type Leases and Direct Financing Leases, Executory Costs Capital Leases Net Investment In Sales Type Leases And Direct Financing Leases Executory Costs Executory costs Capital Leases, Net Investment in Sales Type Leases and Direct Financing Leases, Unearned Income Capital Leases Net Investment In Sales Type Leases And Direct Financing Leases Unearned Income Unearned income Capital Leases, Net Investment in Sales Type Leases and Direct Financing Leases, Unguaranteed Residual Values Capital Leases Net Investment In Sales Type Leases And Direct Financing Leases Unguaranteed Residual Values Unguaranteed residual values Capital Transaction with Noncontrolling Interest and Other Capital Transaction With Noncontrolling Interest And Other Equity transactions with noncontrolling interests and other Carrying Amounts and Fair Values of Financial Instruments [Line Items] Carrying Amounts And Fair Values Of Financial Instruments [Line Items] Carrying Amounts and Fair Values of Financial Instruments [Line Items] Carrying Amounts and Fair Values of Financial Instruments [Table] Carrying Amounts And Fair Values Of Financial Instruments [Table] Carrying Amounts and Fair Values of Financial Instruments [Table] Carrying Reported Amount Fair Value Disclosure [Member] Carrying (Reported) Amount, Fair Value Disclosure Cash And Cash Equivalents At Carrying Value Cash and cash equivalents at end of year Cash and cash equivalents at beginning of year Cash and cash equivalents (Note 1) Cash And Cash Equivalents Fair Value Disclosure Cash and cash equivalents Cash And Cash Equivalents Period Increase Decrease Net change in cash and cash equivalents Cash And Cash Equivalents Policy [Text Block] Cash Equivalents Cash Equivalents At Carrying Value Cash equivalents Cash Equivalents, Maturity Period Cash Equivalents Maturity Period Cash equivalents, maturity period Cash Flow Hedging [Member] Cash Flow Hedging Cash Flow Supplemental Disclosures [Line Items] Cash Flow Supplemental Disclosures [Line Items] Cash Flow Supplemental Disclosures [Line Items] Cash Flow Supplemental Disclosures [Table] Cash Flow Supplemental Disclosures [Table] Cash Flow Supplemental Disclosures [Table] Cash Flow Supplemental Disclosures [Text Block] Supplemental Cash Flow Information Cash Paid During Period For [Abstract] Cash Paid During Period For [Abstract] Cash paid during the year for: Commitments And Contingencies Commitments and contingent liabilities (Note 18) Commitments and Contingencies Disclosure [Line Items] Commitments And Contingencies Disclosure [Line Items] Commitments and Contingencies Disclosure [Line Items] Commitments and Contingencies Disclosure [Table] Commitments And Contingencies Disclosure [Table] Commitments and Contingencies Disclosure [Table] Commitments And Contingencies Disclosure [Text Block] Commitments and Contingent Liabilities Common Stock Dividends Per Share Cash Paid Cash dividends per share Common Stock [Member] Common stock Common Stock Shares Authorized Common stock, shares authorized Common Stock Shares Issued Common stock, shares issued Common Stock Value Common stock Authorized 3,000,000,000 shares; issued 1,333,763,464 shares in 2011 and 2010 Compensation Related Costs Policy [Text Block] Stock-Based Compensation Compensation Related Costs Share Based Payments Disclosure [Line Items] Compensation Related Costs Share Based Payments Disclosure [Line Items] Compensation Related Costs Share Based Payments Disclosure [Line Items] Compensation Related Costs Share Based Payments Disclosure [Table] Compensation Related Costs Share Based Payments Disclosure [Table] Compensation Related Costs Share Based Payments Disclosure [Table] Comprehensive Income (Loss) [Line Items] Comprehensive Income Loss [Line Items] Comprehensive Income (Loss) [Line Items] Comprehensive Income (Loss) [Table] Comprehensive Income Loss [Table] Comprehensive Income (Loss) [Table] Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest Total comprehensive income (loss) Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest [Abstract] Comprehensive income (loss): Comprehensive Income Note [Text Block] Other Comprehensive Income (Loss) Computer Software Intangible Asset [Member] Computer Software, Intangible Asset Consolidation Policy [Text Block] Principles of Consolidation Construction In Progress Gross Construction in progress Consumer Business Unit [Member] Consumer Business Unit [Member] Consumer Business Unit Corporate Bond Securities [Member] Corporate Bonds Cost Method Investments Aggregate Carrying Amount Aggregate cost of non-marketable equity securities accounted for under the cost method Cost Method Investments Aggregate Carrying Amount Not Evaluated For Impairment Aggregate cost of investments not evaluated for impairment Cost Of Revenue Cost of sales (Notes 5, 8, 11 and 18) Costs And Expenses Operating cost and expenses Cumulative Translation Adjustment Net Of Tax Period Increase Decrease Adjustments for the year Cumulative Translation Adjustment Summary [Roll Forward] Foreign currency translation adjustments: Current Fiscal Year End Date Current Fiscal Year End Date Current Income Tax Expense Benefit Current Customer Relationships [Member] Customer Relationships Debt Current Short-term loans and current portion of long-term debt (Note 9) Debt Disclosure [Line Items] Debt Disclosure [Line Items] Debt Disclosure [Line Items] Debt Disclosure [Table] Debt Disclosure [Table] Debt Disclosure [Table] Debt Disclosure [Text Block] Short-Term Loans and Long-Term Debt Debt Instrument Interest Rate Stated Percentage Stated Interest Rate Debt Instrument Maturity Date Year Debt Instrument Maturity Date Year Long-term debt, maturity year Debt Outstanding [Line Items] Debt Outstanding [Line Items] Debt Outstanding [Line Items] Deferred Income Tax Expense Benefit Deferred Deferred income taxes Deferred Tax Assets, Accrued Business Tax Deferred Tax Assets Accrued Business Tax Accrued business tax Deferred Tax Assets, Accrued Expenses Deferred Tax Assets Accrued Expenses Accrued expenses Deferred Tax Assets and Liabilities [Axis] Deferred Tax Assets And Liabilities [Axis] Deferred Tax Assets and Liabilities [Axis] Deferred Tax Assets and Liabilities [Domain] Deferred Tax Assets And Liabilities [Domain] Deferred Tax Assets and Liabilities [Domain] Research and development costs capitalized for tax purposes. Deferred Tax Assets Capitalized Research And Development Expenditures Research and development-costs capitalized for tax purposes Deferred Tax Assets Gross Deferred Tax Assets, Gross, Total Deferred Tax Assets Inventory Inventories Deferred Tax Assets Liabilities Net Net deferred tax assets Deferred Tax Assets Net Total deferred tax assets Deferred Tax Assets Net [Abstract] Deferred tax assets: Deferred Tax Assets Net Current Prepaid expenses and other current assets Deferred Tax Assets Net Noncurrent Other assets Deferred Tax Assets Operating Loss Carryforwards Net operating losses carried forward Deferred Tax Assets Other Other Deferred Tax Assets, Property Plant And Equipment Deferred Tax Assets Property Plant And Equipment Property, plant and equipment Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Pensions Accrued pension and severance cost Deferred Tax Assets Valuation Allowance Less valuation allowance Deferred Tax Liabilities Total deferred tax liabilities Deferred Tax Liabilities [Abstract] Deferred tax liabilities: Deferred Tax Liabilities Current Other current liabilities Deferred Tax Liabilities, Financing Lease Revenue Deferred Tax Liabilities Financing Lease Revenue Financing lease revenue Deferred Tax Liabilities Noncurrent Other noncurrent liabilities Deferred Tax Liabilities Other Other Deferred Tax Liabilities Prepaid Pension Costs Prepaid pension and severance cost