Reportable Segments (Reportable Segments) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Segment net sales	$ 3,007	$ 2,969	$ 8,124	$ 8,805
Depreciation			1,041	1,026
Research, development and engineering expenses	231	255	922	753
Income tax (provision) benefit	(23)	(71)	(33)	(271)
Net income (loss) attributable to Corning Incorporated	$ 427	$ 337	$ 260	$ 928
Statutory U.S. income tax rate	21.00%	21.00%	21.00%	21.00%
Operating Segments [Member]
Segment net sales	$ 3,007	$ 2,969	$ 8,124	$ 8,805
Depreciation	293	295	882	898
Research, development and engineering expenses	177	206	567	633
Income tax (provision) benefit	(136)	(122)	(275)	(359)
Net income (loss) attributable to Corning Incorporated	504	454	1,028	1,342
Display Technologies [Member] | Operating Segments [Member]
Segment net sales	827	793	2,331	2,459
Depreciation	134	144	400	445
Research, development and engineering expenses	22	30	77	85
Income tax (provision) benefit	(52)	(49)	(133)	(159)
Net income (loss) attributable to Corning Incorporated	196	185	500	606
Optical Communications [Member] | Operating Segments [Member]
Segment net sales	909	1,007	2,587	3,161
Depreciation	59	59	183	178
Research, development and engineering expenses	50	53	157	163
Income tax (provision) benefit	(32)	(35)	(63)	(117)
Net income (loss) attributable to Corning Incorporated	115	127	225	427
Specialty Materials [Member] | Operating Segments [Member]
Segment net sales	570	463	1,339	1,141
Depreciation	40	35	120	107
Research, development and engineering expenses	39	37	113	119
Income tax (provision) benefit	(38)	(25)	(76)	(56)
Net income (loss) attributable to Corning Incorporated	146	92	287	208
Environmental Technologies [Member] | Operating Segments [Member]
Segment net sales	379	397	925	1,125
Depreciation	32	32	99	95
Research, development and engineering expenses	24	29	74	87
Income tax (provision) benefit	(18)	(21)	(27)	(53)
Net income (loss) attributable to Corning Incorporated	69	79	104	199
Life Sciences [Member] | Operating Segments [Member]
Segment net sales	223	256	724	759
Depreciation	12	12	37	37
Research, development and engineering expenses	7	5	20	15
Income tax (provision) benefit	(8)	(11)	(26)	(30)
Net income (loss) attributable to Corning Incorporated	28	41	97	112
All Other [Member] | Operating Segments [Member]
Segment net sales	99	53	218	160
Depreciation	16	13	43	36
Research, development and engineering expenses	35	52	126	164
Income tax (provision) benefit	12	19	50	56
Net income (loss) attributable to Corning Incorporated	$ (50)	$ (70)	$ (185)	$ (210)