Reportable Segments (Reportable Segments) (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Segment net sales		$ 2,940	$ 2,747	$ 5,752	$ 5,247
Depreciation				658	604
Research, development and engineering expenses		249	243	498	484
Income tax benefit (provision)		(124)	(126)	(200)	(250)
Net income (loss) attributable to Corning Incorporated		$ 92	$ 738	$ 591	$ 149
Statutory U.S. income tax rate		21.00%	21.00%	21.00%	21.00%
Operating Segments [Member]
Segment net sales		$ 2,986	$ 2,759	$ 5,836	$ 5,272
Depreciation	[1]	300	287	603	570
Research, development and engineering expenses	[2]	214	212	427	414
Income tax benefit (provision)	[3]	(126)	(110)	(237)	(202)
Net income (loss) attributable to Corning Incorporated	[4]	475	413	888	758
Display Technologies [Member] | Operating Segments [Member]
Segment net sales		848	780	1,666	1,525
Depreciation	[1]	149	146	301	290
Research, development and engineering expenses	[2]	29	27	55	50
Income tax benefit (provision)	[3]	(55)	(51)	(110)	(100)
Net income (loss) attributable to Corning Incorporated	[4]	213	192	421	377
Optical Communications [Member] | Operating Segments [Member]
Segment net sales		1,090	1,023	2,154	1,909
Depreciation	[1]	60	53	119	105
Research, development and engineering expenses	[2]	54	51	110	100
Income tax benefit (provision)	[3]	(43)	(41)	(82)	(71)
Net income (loss) attributable to Corning Incorporated	[4]	158	150	300	259
Specialty Materials [Member] | Operating Segments [Member]
Segment net sales		369	343	678	621
Depreciation	[1]	35	35	72	68
Research, development and engineering expenses	[2]	41	41	82	80
Income tax benefit (provision)	[3]	(18)	(17)	(31)	(29)
Net income (loss) attributable to Corning Incorporated	[4]	67	64	116	110
Environmental Technologies [Member] | Operating Segments [Member]
Segment net sales		366	317	728	639
Depreciation	[1]	32	30	63	59
Research, development and engineering expenses	[2]	28	29	58	58
Income tax benefit (provision)	[3]	(17)	(14)	(32)	(28)
Net income (loss) attributable to Corning Incorporated	[4]	65	54	120	106
Life Sciences [Member] | Operating Segments [Member]
Segment net sales		260	245	503	477
Depreciation	[1]	12	13	25	27
Research, development and engineering expenses	[2]	5	5	10	10
Income tax benefit (provision)	[3]	(11)	(8)	(19)	(15)
Net income (loss) attributable to Corning Incorporated	[4]	40	31	71	58
All Other [Member] | Operating Segments [Member]
Segment net sales		53	51	107	101
Depreciation	[1]	12	10	23	21
Research, development and engineering expenses	[2]	57	59	112	116
Income tax benefit (provision)	[3]	18	21	37	41
Net income (loss) attributable to Corning Incorporated	[4]	$ (68)	$ (78)	$ (140)	$ (152)

[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] Income tax provision (benefit) reflects a tax rate of 21%.

[4] 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.