Note 14 - Reportable Segments - Reportable Segments (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2023	Mar. 31, 2022
Depreciation (1)		$ 310	$ 342
Research, development and engineering expenses (2)		254	248
Income tax provision (3)		37	180
Net income of reportable segments		176	581
Operating Segments [Member]
Net sales of reportable segments		3,367	3,744
Depreciation (1)	[1]	307	340
Research, development and engineering expenses (2)	[2]	209	213
Income tax provision (3)	[3]	(128)	(160)
Net income of reportable segments		465	585
Optical Communications [Member] | Operating Segments [Member]
Net sales of reportable segments		1,125	1,198
Depreciation (1)	[1]	66	59
Research, development and engineering expenses (2)	[2]	60	55
Income tax provision (3)	[3]	(43)	(45)
Net income of reportable segments		159	166
Display Products [Member] | Operating Segments [Member]
Net sales of reportable segments		763	959
Depreciation (1)	[1]	123	156
Research, development and engineering expenses (2)	[2]	23	31
Income tax provision (3)	[3]	(42)	(63)
Net income of reportable segments		160	236
Specialty Materials [Member] | Operating Segments [Member]
Net sales of reportable segments		406	493
Depreciation (1)	[1]	35	40
Research, development and engineering expenses (2)	[2]	53	53
Income tax provision (3)	[3]	(10)	(20)
Net income of reportable segments		39	75
Environmental Technologies [Member] | Operating Segments [Member]
Net sales of reportable segments		431	409
Depreciation (1)	[1]	33	33
Research, development and engineering expenses (2)	[2]	24	25
Income tax provision (3)	[3]	(22)	(20)
Net income of reportable segments		82	74
Life Science Products [Member] | Operating Segments [Member]
Net sales of reportable segments		256	310
Depreciation (1)	[1]	17	14
Research, development and engineering expenses (2)	[2]	10	9
Income tax provision (3)	[3]	(2)	(11)
Net income of reportable segments		9	42
Hemlock and Emerging Growth Businesses [Member]
Net sales of reportable segments		386	375
Depreciation (1)	[1]	33	38
Research, development and engineering expenses (2)	[2]	39	40
Income tax provision (3)	[3]	(9)	(1)
Net income of reportable segments		$ 16	$ (8)

[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%.