Note 14 - Reportable Segments - Reportable Segments (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023		Jun. 30, 2022
Depreciation (1)			$ 622		$ 687
Research, development and engineering expenses (2)	$ 263	$ 240	517		488
Income tax provision (3)	106	166	143		346
Net income of reportable segments	281	563	457		1,144
Operating Segments [Member]
Net sales of reportable segments	3,482	3,762	6,849		7,506
Depreciation (1)	307	341	614		681
Research, development and engineering expenses (2)	209	203	418		416
Income tax provision (3)	(144)	(170)	(272)		(330)
Net income of reportable segments	525	625	990		1,210
Optical Communications [Member] | Operating Segments [Member]
Net sales of reportable segments	1,066	1,313	2,191		2,511
Depreciation (1)	64	68	130		127
Research, development and engineering expenses (2)	56	58	116		113
Income tax provision (3)	(38)	(51)	(81)	[1]	(96)
Net income of reportable segments	140	182	299		348
Display Products [Member] | Operating Segments [Member]
Net sales of reportable segments	928	878	1,691		1,837
Depreciation (1)	120	146	243		302
Research, development and engineering expenses (2)	24	30	47		61
Income tax provision (3)	(55)	(59)	(97)		(122)
Net income of reportable segments	208	228	368		464
Specialty Materials [Member] | Operating Segments [Member]
Net sales of reportable segments	423	485	829		978
Depreciation (1)	39	42	74		82
Research, development and engineering expenses (2)	57	44	110	[2]	97
Income tax provision (3)	(9)	(24)	(19)		(44)
Net income of reportable segments	33	91	72		166
Environmental Technologies [Member] | Operating Segments [Member]
Net sales of reportable segments	457	356	888		765
Depreciation (1)	32	34	65	[3]	67
Research, development and engineering expenses (2)	23	24	47		49
Income tax provision (3)	(28)	(16)	(50)		(36)
Net income of reportable segments	107	62	189		136
Life Science Products [Member] | Operating Segments [Member]
Net sales of reportable segments	231	312	487		622
Depreciation (1)	17	16	34		30
Research, development and engineering expenses (2)	8	9	18		18
Income tax provision (3)	(3)	(10)	(5)		(21)
Net income of reportable segments	11	37	20		79
Hemlock and Emerging Growth Businesses [Member]
Net sales of reportable segments	377	418	763		793
Depreciation (1)	35	35	68		73
Research, development and engineering expenses (2)	41	38	80		78
Income tax provision (3)	(11)	(10)	(20)		(11)
Net income of reportable segments	$ 26	$ 25	$ 42		$ 17

[1] Income tax provision reflects a tax rate of 21%.

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

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