Reportable Segments (Reportable Segments) (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Net sales		$ 3,008	$ 2,607	$ 8,255	$ 7,479
Depreciation				895	799
Research, development and engineering expenses		244	215	728	623
Income tax (provision) benefit		(133)	(89)	(383)	(176)
Net income		625	390	774	915
Operating Segments [Member]
Net sales		3,045	2,635	8,317	7,583
Depreciation	[1]	(287)	274	857	795
Research, development and engineering expenses	[2]	213	190	627	550
Income tax (provision) benefit		(139)	(114)	(341)	(340)
Net income	[3]	520	430	1,278	1,272
Display Technologies [Member] | Operating Segments [Member]
Net sales		852	795	2,377	2,354
Depreciation	[1]	(146)	134	436	393
Research, development and engineering expenses	[2]	26	21	76	63
Income tax (provision) benefit		(57)	(56)	(157)	(180)
Net income	[3]	218	211	595	682
Optical Communications [Member] | Operating Segments [Member]
Net sales		1,117	917	3,026	2,617
Depreciation	[1]	(55)	49	160	142
Research, development and engineering expenses	[2]	53	44	153	121
Income tax (provision) benefit		(46)	(35)	(117)	(100)
Net income	[3]	168	132	427	370
Specialty Materials [Member] | Operating Segments [Member]
Net sales		459	373	1,080	1,010
Depreciation	[1]	(34)	34	102	94
Research, development and engineering expenses	[2]	43	38	123	111
Income tax (provision) benefit		(31)	(22)	(60)	(56)
Net income	[3]	116	86	226	213
Environmental Technologies [Member] | Operating Segments [Member]
Net sales		331	277	970	815
Depreciation	[1]	(30)	31	89	93
Research, development and engineering expenses	[2]	28	28	86	80
Income tax (provision) benefit		(16)	(11)	(44)	(33)
Net income	[3]	60	40	166	122
Life Sciences [Member] | Operating Segments [Member]
Net sales		231	223	708	654
Depreciation	[1]	(12)	14	39	39
Research, development and engineering expenses	[2]	5	6	15	18
Income tax (provision) benefit		(8)	(7)	(23)	(19)
Net income	[3]	30	25	88	71
All Other [Member] | Operating Segments [Member]
Net sales		55	50	156	133
Depreciation	[1]	(10)	12	31	34
Research, development and engineering expenses	[2]	58	53	174	157
Income tax (provision) benefit		19	17	60	48
Net income	[3]	$ (72)	$ (64)	$ (224)	$ (186)

[1] Depreciation expense for Corning's reportable segments includes an allocation of depreciation of corporate property not specifically identifiable to a segment.

[2] Research, development and engineering expenses include direct project spending that is identifiable to a segment.

[3] Many of Corning's administrative and staff functions are performed on a centralized basis. Where practicable, Corning charges these expenses to segments based upon the extent to which each business uses a centralized function. Other staff functions, such as corporate finance, human resources and legal, are allocated to segments, primarily as a percentage of sales. Expenses that are not allocated to the segments are included in the reconciliation of reportable segment net income to consolidated net income below.