2.2.0.25truefalse40301 - Disclosure - Debt (Narrative) (Details)truefalsefalse1falsefalseUSDfalsefalse3/31/2011 USD ($) USD ($) / shares $As_Of_3_31_2011http://www.sec.gov/CIK0001037016instant2011-03-31T00:00:000001-01-01T00:00:00Unit1Standardhttp://www.xbrl.org/2003/instancesharesxbrli0Unit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170Unit14Dividehttp://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2003/instancesharesxbrli0Unit13Standardhttp://www.xbrl.org/2003/instancepurexbrli0USDUSD$2falsefalseUSDtruefalse{us-gaap_LongtermDebtTypeAxis} : 7.625% Senior Notes Due 2021 [Member] 1/1/2011 - 3/31/2011 USD ($) $Duration_1_1_2011_To_3_31_2011_us-gaap_LongtermDebtTypeAxis_nihd_SevenPointSixTwoFivePercentSeniorNotesDueTwoThousandTwentyOneMemberhttp://www.sec.gov/CIK0001037016duration2011-01-01T00:00:002011-03-31T00:00:00falsefalse7.625% Senior Notes Due 2021 [Member]us-gaap_LongtermDebtTypeAxisxbrldihttp://xbrl.org/2006/xbrldinihd_SevenPointSixTwoFivePercentSeniorNotesDueTwoThousandTwentyOneMemberus-gaap_LongtermDebtTypeAxisexplicitMemberUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170Unit13Standardhttp://www.xbrl.org/2003/instancepurexbrli0USDUSD$3falsefalsetruefalse{us-gaap_LongtermDebtTypeAxis} : 8.875% Senior Notes Due 2019 [Member] 3/31/2011 As_Of_3_31_2011_us-gaap_LongtermDebtTypeAxis_nihd_EightPointEightSevenFivePercentSeniorNotesDueTwoThousandNineteenMemberhttp://www.sec.gov/CIK0001037016instant2011-03-31T00:00:000001-01-01T00:00:00falsefalse8.875% Senior Notes Due 2019 [Member]us-gaap_LongtermDebtTypeAxisxbrldihttp://xbrl.org/2006/xbrldinihd_EightPointEightSevenFivePercentSeniorNotesDueTwoThousandNineteenMemberus-gaap_LongtermDebtTypeAxisexplicitMemberUnit13Standardhttp://www.xbrl.org/2003/instancepurexbrli04falsefalseUSDtruefalse{us-gaap_LongtermDebtTypeAxis} : 3.125% Convertible Notes Due 2012 [Member] 1/1/2011 - 3/31/2011 USD ($) USD ($) / shares $Duration_1_1_2011_To_3_31_2011_us-gaap_LongtermDebtTypeAxis_nihd_ThreePointOneTwoFivePercentConvertibleNotesDueTwoZeroOneTwoMemberhttp://www.sec.gov/CIK0001037016duration2011-01-01T00:00:002011-03-31T00:00:00falsefalse3.125% Convertible Notes Due 2012 [Member]us-gaap_LongtermDebtTypeAxisxbrldihttp://xbrl.org/2006/xbrldinihd_ThreePointOneTwoFivePercentConvertibleNotesDueTwoZeroOneTwoMemberus-gaap_LongtermDebtTypeAxisexplicitMemberUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170Unit1Standardhttp://www.xbrl.org/2003/instancesharesxbrli0Unit14Dividehttp://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2003/instancesharesxbrli0Unit13Standardhttp://www.xbrl.org/2003/instancepurexbrli0USDUSD$5falsefalsetruefalse{us-gaap_LongtermDebtTypeAxis} : 2.75% Convertible Notes Due 2025 [Member] 3/31/2011 As_Of_3_31_2011_us-gaap_LongtermDebtTypeAxis_nihd_TwoPointSevenFivePercentConvertibleNotesDueTwoZeroTwoFiveMemberhttp://www.sec.gov/CIK0001037016instant2011-03-31T00:00:000001-01-01T00:00:00falsefalse2.75% Convertible Notes Due 2025 [Member]us-gaap_LongtermDebtTypeAxisxbrldihttp://xbrl.org/2006/xbrldinihd_TwoPointSevenFivePercentConvertibleNotesDueTwoZeroTwoFiveMemberus-gaap_LongtermDebtTypeAxisexplicitMemberUnit13Standardhttp://www.xbrl.org/2003/instancepurexbrli06falsefalsetruefalse{us-gaap_LongtermDebtTypeAxis} : 10.0% Senior Notes Due 2016 [Member] 3/31/2011 As_Of_3_31_2011_us-gaap_LongtermDebtTypeAxis_nihd_TenPointZeroPercentSeniorNotesDueTwoZeroOneSixMemberhttp://www.sec.gov/CIK0001037016instant2011-03-31T00:00:000001-01-01T00:00:00falsefalse10.0% Senior Notes Due 2016 [Member]us-gaap_LongtermDebtTypeAxisxbrldihttp://xbrl.org/2006/xbrldinihd_TenPointZeroPercentSeniorNotesDueTwoZeroOneSixMemberus-gaap_LongtermDebtTypeAxisexplicitMemberUnit13Standardhttp://www.xbrl.org/2003/instancepurexbrli02false0us-gaap_DebtInstrumentFaceAmountus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00falsefalsefalsefalsefalse2truefalsefalse750000000750000000falsetruefalsetruefalse3falsefalsefalse00falsefalsefalsetruefalse4falsefalsefalse00falsefalsefalsetruefalse5falsefalsefalse00falsefalsefalsetruefalse6falsefalsefalse00falsefalsefalsetruefalseMonetaryxbrli:monetaryItemTypemonetaryThe stated principal amount of the debt instrument at time of issuance, which may vary from the carrying amount because of unamortized premium or discount.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 21 -Paragraph 16, 20 falsefalsePrincipal amount3false0us-gaap_ProceedsFromNotesPayableus-gaaptruedebitdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00falsefalsefalsefalsefalse2truefalsefalse735800000735800000falsefalsefalsetruefalse3falsefalsefalse00falsefalsefalsetruefalse4falsefalsefalse00falsefalsefalsetruefalse5falsefalsefalse00falsefalsefalsetruefalse6falsefalsefalse00falsefalsefalsetruefalseMonetaryxbrli:monetaryItemTypemonetaryThe cash inflow from a borrowing supported by a written promise to pay an obligation.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 18 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 19 -Subparagraph b falsefalseTotal cash proceeds4false0us-gaap_UnamortizedDebtIssuanceExpenseus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00falsefalsefalsefalsefalse2truefalsefalse1420000014200000falsefalsefalsetruefalse3falsefalsefalse00falsefalsefalsetruefalse4falsefalsefalse00falsefalsefalsetruefalse5falsefalsefalse00falsefalsefalsetruefalse6falsefalsefalse00falsefalsefalsetruefalseMonetaryxbrli:monetaryItemTypemonetaryThe remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. 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