Note 17 - Reportable Segments - Reportable Segments (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Operating Segments [Member] | Display Technologies [Member]
Net sales		$ 801	$ 789	$ 1,506	$ 1,597
Depreciation	[1]	149	152	300	308
Amortization of purchased intangibles
Research, development and engineering expenses	[2]	17	26	35	50
Restructuring, impairment and other charges		2		16
Equity in earnings of affiliated companies			(3)		(5)
Income tax (provision) benefit		(86)	(136)	(179)	(268)
Net income	[3]	204	303	413	597
Operating Segments [Member] | Optical Communications [Member]
Net sales		782	800	1,391	1,497
Depreciation	[1]	43	43	84	81
Amortization of purchased intangibles		8	11	15	17
Research, development and engineering expenses	[2]	36	35	73	68
Restructuring, impairment and other charges				6	(1)
Equity in earnings of affiliated companies
Income tax (provision) benefit		(39)	(37)	(50)	(66)
Net income	[3]	77	77	94	94
Operating Segments [Member] | Environmental Technologies [Member]
Net sales		259	260	523	542
Depreciation	[1]	33	32	65	61
Amortization of purchased intangibles
Research, development and engineering expenses	[2]	26	23	51	46
Restructuring, impairment and other charges				5
Equity in earnings of affiliated companies
Income tax (provision) benefit		(19)	(22)	(35)	(45)
Net income	[3]	37	46	71	134
Operating Segments [Member] | Specialty Materials [Member]
Net sales		266	272	493	544
Depreciation	[1]	27	27	55	53
Amortization of purchased intangibles
Research, development and engineering expenses	[2]	34	29	65	60
Restructuring, impairment and other charges		12	3	24	3
Equity in earnings of affiliated companies
Income tax (provision) benefit		(19)	(22)	(31)	(43)
Net income	[3]	38	44	64	82
Operating Segments [Member] | Life Sciences [Member]
Net sales		215	211	419	408
Depreciation	[1]	13	15	28	30
Amortization of purchased intangibles		5	5	10	10
Research, development and engineering expenses	[2]	6	6	12	11
Restructuring, impairment and other charges		1		5
Equity in earnings of affiliated companies
Income tax (provision) benefit		(8)	(9)	(14)	(17)
Net income	[3]	17	18	29	34
Operating Segments [Member] | Other Segments [Member]
Net sales		37	11	75	20
Depreciation	[1]	11	11	22	20
Amortization of purchased intangibles		2		4
Research, development and engineering expenses	[2]	45	44	92	89
Restructuring, impairment and other charges		1		61
Equity in earnings of affiliated companies		(8)	6	(5)	8
Income tax (provision) benefit		23	21	66	44
Net income	[3]	(55)	(45)	(140)	(93)
Operating Segments [Member]
Net sales		2,360	2,343	4,407	4,608
Depreciation	[1]	276	280	554	553
Amortization of purchased intangibles		15	16	29	27
Research, development and engineering expenses	[2]	164	163	328	324
Restructuring, impairment and other charges		16	3	117	2
Equity in earnings of affiliated companies		(8)	3	(5)	3
Income tax (provision) benefit		(148)	(205)	(243)	(395)
Net income	[3]	318	443	531	848
Display Technologies [Member]
Restructuring, impairment and other charges				4
Optical Communications [Member]
Restructuring, impairment and other charges				6
Environmental Technologies [Member]
Restructuring, impairment and other charges				5
Specialty Materials [Member]
Restructuring, impairment and other charges				12
Life Sciences [Member]
Restructuring, impairment and other charges				3
Other Segments [Member]
Restructuring, impairment and other charges				40
Net sales		2,360	2,343	4,407	4,608
Depreciation				561	562
Amortization of purchased intangibles		15	16	29	28
Research, development and engineering expenses		192	191	382	380
Restructuring, impairment and other charges		(2)		78
Equity in earnings of affiliated companies		41	62	100	156
Income tax (provision) benefit		(504)	110	(808)	196
Net income		$ 2,207	$ 496	$ 1,839	$ 903

[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 net segment net income to consolidated net income below.