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The portion of the expected postretirement benefit obligation attributed to employee service during the period. The service cost component is a portion of the benefit obligation and is unaffected by the funded status of the plan.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 106 -Paragraph 518 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 264 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph a, h falsefalseService cost3false0us-gaap_DefinedBenefitPlanInterestCostus-gaaptruedebitdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2truefalsefalse5000000050falsefalsefalsetruefalse3truefalsefalse5100000051falsefalsefalsetruefalse4truefalsefalse4700000047falsefalsefalsetruefalse5truefalsefalse157000000157falsefalsefalsetruefalse6truefalsefalse157000000157falsefalsefalsetruefalse7truefalsefalse150000000150falsefalsefalsetruefalseMonetaryxbrli:monetaryItemTypemonetaryThe increase in a defined benefit pension plan's projected benefit obligation or a defined benefit postretirement plan's accumulated postretirement benefit obligation due to the passage of time.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 106 -Paragraph 518 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 264 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph a, h falsefalseInterest cost4false0us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssetsus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsetruefalse3falsefalsefalse00falsefalsefalsetruefalse4falsefalsefalse00falsefalsefalsetruefalse5truefalsefalse-168000000-168falsefalsefalsetruefalse6truefalsefalse-179000000-179falsefalsefalsetruefalse7truefalsefalse-196000000-196falsefalsefalsetruefalseMonetaryxbrli:monetaryItemTypemonetaryAn amount calculated as a basis for determining the extent of delayed recognition of the effects of changes in the fair value of assets. The expected return on plan assets is determined based on the expected long-term rate of return on plan assets and the market-related value of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 106 -Paragraph 518 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 264 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph h falsefalseExpected return on plan assets5false0us-gaap_DefinedBenefitPlanAmortizationOfGainsLossesus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2truefalsefalse1500000015falsefalsefalsetruefalse3truefalsefalse1100000011falsefalsefalsetruefalse4truefalsefalse80000008falsefalsefalsetruefalse5truefalsefalse5000000050falsefalsefalsetruefalse6truefalsefalse3100000031falsefalsefalsetruefalse7truefalsefalse1400000014falsefalsefalsetruefalseMonetaryxbrli:monetaryItemTypemonetaryThe amount of gains or losses recognized in net periodic benefit costReference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph h falsefalseAmortization of net loss6false0us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCreditus-gaaptruedebitdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalselabel1falsefalsefalse00falsefalsefalsefalsefalse2truefalsefalse-6000000-6falsefalsefalsetruefalse3truefalsefalse-3000000-3falsefalsefalsetruefalse4truefalsefalse-3000000-3falsefalsefalsetruefalse5truefalsefalse90000009falsefalsefalsetruefalse6truefalsefalse80000008falsefalsefalsetruefalse7truefalsefalse1000000010falsefalsefalsetruefalseMonetaryxbrli:monetaryItemTypemonetaryThe amount of the prior service cost or credit recognized in net periodic benefit cost relating to benefit changes attributable to plan participants' prior service pursuant to a plan amendment or a plan initiation.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph h falsefalseAmortization of prior service cost (credit)7false0glw_TotalPensionAndPostretirementBenefitExpenseglwfalsedebitdurationThe total amount of net periodic benefit cost for defined benefit plans for the period. Periodic benefit costs include the...falsefalsefalsefalsefalsefalsefalsefalsefalsefalsetotallabel1falsefalsefalse00falsefalsefalsefalsefalse2truefalsefalse7100000071falsefalsefalsetruefalse3truefalsefalse7000000070falsefalsefalsetruefalse4truefalsefalse6400000064falsefalsefalsetruefalse5truefalsefalse9400000094falsefalsefalsetruefalse6truefalsefalse6300000063falsefalsefalsetruefalse7truefalsefalse2900000029falsefalsefalsetruefalseMonetaryxbrli:monetaryItemTypemonetaryThe total amount of net periodic benefit cost for defined benefit plans for the period. 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Periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain or loss, prior service cost or credit, transition asset or obligation, and gain or loss due to settlements or curtailments).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph h truefalseTotal expense10false0glw_OtherComprehensiveIncomeReclassificationOfDefinedBenefitPlansNetGainLossRecognizedInNetPeriodicBenefitCostCurtailmentEffectsglwfalsecreditdurationOther Comprehensive Income Reclassification Of Defined Benefit Plans Net Gain Loss Recognized In Net Periodic Benefit 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