CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) shares in Millions, $ in Millions		Total	Common Stock Outstanding	Treasury Stock	APIC		Accumulated Earnings	AOCI		NCI
Beginning balance at Dec. 31, 2017		$ 4,204	$ 1	$ (911)	$ 4,011	[1]	$ 1,575	$ (514)	[2]	$ 42	[3]
Beginning balance (in shares) at Dec. 31, 2017			111.5	24.0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings attributable to Owens Corning		92					92
Currency translation adjustment		(14)						(15)	[2]	1	[3]
Pension and other postretirement adjustment (net of tax)		(2)						(2)	[2]
Deferred loss on hedging transactions (net of tax)		1						1	[2]
Issuance of common stock under share-based payment plans, shares			0.6	(0.6)
Issuance of common stock under share-based payment plans		0		$ 21	(21)	[1]
Purchases of treasury stock (shares)			(1.1)	1.1
Purchases of treasury stock		(113)		$ (113)
Stock-based compensation expense		9			9	[1]
Dividends declared	[4]	(24)					(24)
Ending balance at Mar. 31, 2018		4,141	$ 1	$ (1,003)	3,999	[1]	1,631	(530)	[2]	43	[3]
Ending balance (in shares) at Mar. 31, 2018			111.0	24.5
Beginning balance at Dec. 31, 2017		4,204	$ 1	$ (911)	4,011	[1]	1,575	(514)	[2]	42	[3]
Beginning balance (in shares) at Dec. 31, 2017			111.5	24.0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings attributable to Owens Corning		213
Net earnings attributable to noncontrolling interests		1
Ending balance at Jun. 30, 2018		4,167	$ 1	$ (1,013)	4,009	[1]	1,729	(600)	[2]	41	[3]
Ending balance (in shares) at Jun. 30, 2018			110.9	24.6
Beginning balance at Mar. 31, 2018		4,141	$ 1	$ (1,003)	3,999	[1]	1,631	(530)	[2]	43	[3]
Beginning balance (in shares) at Mar. 31, 2018			111.0	24.5
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings attributable to Owens Corning		121					121
Net earnings attributable to noncontrolling interests		1								1	[3]
Currency translation adjustment		(76)						(74)	[2]	(2)	[3]
Pension and other postretirement adjustment (net of tax)		4						4	[2]
Issuance of common stock under share-based payment plans, shares			0.2	(0.2)
Issuance of common stock under share-based payment plans		10		$ 13	(3)	[1]
Purchases of treasury stock (shares)			(0.3)	0.3
Purchases of treasury stock		(23)		$ (23)
Stock-based compensation expense		13			13	[1]
Dividends declared	[4]	(24)					(23)			(1)	[3]
Ending balance at Jun. 30, 2018		4,167	$ 1	$ (1,013)	4,009	[1]	1,729	(600)	[2]	41	[3]
Ending balance (in shares) at Jun. 30, 2018			110.9	24.6
Beginning balance at Dec. 31, 2018		4,324	$ 1	$ (1,103)	4,028		2,013	(656)		41
Beginning balance (in shares) at Dec. 31, 2018			109.5	26.0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings attributable to Owens Corning		44					44			0	[5]
Currency translation adjustment		10						11	[6]	(1)	[5]
Pension and other postretirement adjustment (net of tax)		(1)						(1)	[6]
Deferred loss on hedging transactions (net of tax)		(1)						(1)	[6]
Issuance of common stock under share-based payment plans, shares			0.4	(0.4)
Issuance of common stock under share-based payment plans		0		$ 14	(14)	[7]
Purchases of treasury stock (shares)			(1.3)	(1.3)
Purchases of treasury stock		(61)		$ (61)
Stock-based compensation expense		11			11	[7]
Dividends declared		(24)					(24)
Ending balance at Mar. 31, 2019		4,302	$ 1	$ (1,150)	4,025	[7]	2,033	(647)	[6]	40	[5]
Ending balance (in shares) at Mar. 31, 2019			108.6	26.9
Beginning balance at Dec. 31, 2018		4,324	$ 1	$ (1,103)	4,028		2,013	(656)		41
Beginning balance (in shares) at Dec. 31, 2018			109.5	26.0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings attributable to Owens Corning		182
Net earnings attributable to noncontrolling interests		0
Ending balance at Jun. 30, 2019		4,445	$ 1	$ (1,141)	4,034	[7]	2,146	(635)	[6]	40	[5]
Ending balance (in shares) at Jun. 30, 2019			108.8	26.7
Beginning balance at Mar. 31, 2019		4,302	$ 1	$ (1,150)	4,025	[7]	2,033	(647)	[6]	40	[5]
Beginning balance (in shares) at Mar. 31, 2019			108.6	26.9
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings attributable to Owens Corning		138					138			0	[5]
Net earnings attributable to noncontrolling interests		0
Currency translation adjustment		10						10		0
Pension and other postretirement adjustment (net of tax)		2						2	[6]
Issuance of common stock under share-based payment plans, shares			0.2	(0.2)
Issuance of common stock under share-based payment plans		8		$ 9	(1)	[7]
Stock-based compensation expense		10			10	[7]
Dividends declared		(25)					(25)
Ending balance at Jun. 30, 2019		$ 4,445	$ 1	$ (1,141)	$ 4,034	[7]	$ 2,146	$ (635)	[6]	$ 40	[5]
Ending balance (in shares) at Jun. 30, 2019			108.8	26.7

[1] Additional Paid in Capital (APIC)

[2] Accumulated Other Comprehensive Earnings (Deficit) (“AOCI”)

[3] Noncontrolling Interest (“NCI”)

[4] Cumulative effect of accounting change relates to our adoption of accounting standard updates (ASU) 2014-09, "Revenue from Contracts with Customers (Topic 606)," and ASU 2016-16, "Intra-Entity Transfers of Assets Other Than Inventory (Topic 740)."

[5] Noncontrolling Interest (“NCI”)

[6] Accumulated Other Comprehensive Earnings (Deficit) (“AOCI”)

[7] Additional Paid in Capital (APIC)