Reportable Segments (Reconciliation of Reportable Segment Net Income to Consolidated Net Income (Loss)) (Details) - USD ($) $ in Millions	3 Months Ended				9 Months Ended		12 Months Ended
	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Segment Reporting, Revenue Reconciling Item [Line Items]
Litigation, regulatory and other legal matters	$ (83)			$ 24	$ (108)	$ 24
Research, development, and engineering expenses	(231)			(255)	(922)	(753)
Transaction-related gain, net	498				498
Equity in (losses) earnings of affiliated companies	(76)			23	17	81
Amortization of intangibles	(33)			(28)	(87)	(85)
Interest expense, net	(70)			(55)	(201)	(161)
Income tax (provision) benefit	(23)			(71)	(33)	(271)
Cumulative adjustment related to customer contract			$ 105		(105)
Accelerated depreciation					(1,041)	(1,026)
Severance charges	(6)			(18)	(141)	(25)
Asset impairment	(22)	$ (195)			(217)		$ (369)
Net income attributable to Corning Incorporated	427			337	260	928
Operating Segments [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Research, development, and engineering expenses	(177)			(206)	(567)	(633)
Income tax (provision) benefit	(136)			(122)	(275)	(359)
Accelerated depreciation	(293)			(295)	(882)	(898)
Net income attributable to Corning Incorporated	504			454	1,028	1,342
Operating Segments [Member] | Reportable Segments [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Net income attributable to Corning Incorporated	554			524	1,213	1,552
Operating Segments [Member] | Non Reportable Segments [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Net income attributable to Corning Incorporated	(50)			(70)	(185)	(210)
Segment Reconciling Items [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Impact of foreign currency movements not included in segment net income (loss)				(20)	(25)	(93)
(Loss) gain on foreign currency hedges related to translated earnings	(99)			84	(6)	161
Translation (loss) gain on Japanese yen-denominated debt	(39)			11	(50)	(10)
Research, development, and engineering expenses	(35)			(33)	(111)	(104)
Equity in (losses) earnings of affiliated companies	(79)			20	20	80
Amortization of intangibles	(33)			(28)	(87)	(85)
Interest expense, net	(67)			(51)	(189)	(145)
Income tax (provision) benefit	113			51	242	88
Cumulative adjustment related to customer contract					(105)
Severance charges	(6)			(18)	(141)	(25)
Asset impairment	(22)				(217)
Capacity realignment and other charges and credits	(143)			(130)	(375)	(197)
Other corporate items	(82)			(27)	(114)	(108)
Net income attributable to Corning Incorporated	$ 427			$ 337	$ 260	$ 928