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May include notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, which had initial maturities beyond one year or beyond the normal operating cycle, if longer, and after deducting unamortized discount or premiums, if any.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 16 -Article 7 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 16 -Article 9 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 20, 22 -Article 5 truefalseTotal principal9false0igt_ConvertibleNotesUnamortizedDiscountigtfalsedebitinstantThe amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.falsefalsefalsefalsefalsefalsefalsefalsefalsefalselabel1truefalsefalse-124100000-124.1falsefalsefalsetruefalse2truefalsefalse-152100000-152.1falsefalsefalsetruefalseMonetaryxbrli:monetaryItemTypemonetaryThe amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.No authoritative reference available.falsefalse3.25% Convertible Notes discount10false0us-gaap_DebtInstrumentUnamortizedDiscountus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalselabel1truefalsefalse-2500000-2.5falsefalsefalsetruefalse2truefalsefalse-2600000-2.6falsefalsefalsetruefalseMonetaryxbrli:monetaryItemTypemonetaryThe amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Staff Position (FSP) -Number APB14-1 -Paragraph 31 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 21 -Paragraph 16, 20 falsefalse7.5% Bonds discount11false0igt_BondUnamortizedDiscountigtfalsedebitinstantThe amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse-1200000-1.2falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsetruefalseMonetaryxbrli:monetaryItemTypemonetaryThe amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.No authoritative reference available.falsefalse5.5% Bonds discount12false0igt_DebenturesDiscountigtfalsenadurationThe amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.falsefalsefalsefalsefalsefalsefalsefalsefalsefalselabel1falsefalsefalse00falsefalsefalsetruefalse2truefalsefalse-2700000-2.7falsefalsefalsetruefalseMonetaryxbrli:monetaryItemTypemonetaryThe amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.No authoritative reference available.falsefalseDebentures discount13false0us-gaap_IncreaseDecreaseInFairValueOfInterestRateFairValueHedgingInstrumentsus-gaaptruedebitdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalselabel1truefalsefalse3390000033.9falsefalsefalsetruefalse2truefalsefalse1510000015.1falsefalsefalsetruefalseMonetaryxbrli:monetaryItemTypemonetaryAmount of unrealized gain (loss) related to the fair value of interest rate derivatives designated as fair value hedging instruments. Recognized in earnings and offsets the gain (loss) on the hedged item to the extent that the fair value hedge is determined to be effective.No authoritative reference available.falsefalse7.5% Swap fair value adjustment (see Note 19)14false0igt_SwapFairValueAdjustmentigtfalsedebitdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse1820000018.2falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsetruefalseMonetaryxbrli:monetaryItemTypemonetaryNo definition available.No authoritative reference available.falsefalse5.5% Swap fair value adjustment (see Note 19)15false0us-gaap_LongTermDebtAndCapitalLeaseObligationsus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalsetotallabel1truefalsefalse16743000001674.3falsetruefalsetruefalse2truefalsefalse20200000002020.0falsetruefalsetruefalseMonetaryxbrli:monetaryItemTypemonetarySum of the carrying values as of the balance sheet date of all long-term debt, which is debt initially having maturities due after one year from the balance sheet date or beyond the operating cycle, if longer, but excluding the portions thereof scheduled to be repaid within one year or the normal operating cycle, if longer plus capital lease obligations due to be paid more than one year after the balance sheet date.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 6 -Section H truefalseTotal outstanding debt, net214Credit Facilities and Indebtedness (Detail) (Outstanding Debt [Member], USD $)HundredThousandsUnKnownUnKnownUnKnownfalsetrue