Consolidated Statement of Shareholders' Equity - USD ($) $ in Millions	Total	Common Stock	Additional Paid-In Capital	Retained Earnings	Treasury Stock	Accumulated Other Comprehensive Income/(Loss)	Total PPG	Non-controlling Interests
Beginning balance at Dec. 31, 2012	$ 4,322	$ 484	$ 870	$ 9,871	$ (5,496)	$ (1,666)	$ 4,063	$ 259
Net income attributable to the controlling and noncontrolling interests	3,353			3,231			3,231	122
Other comprehensive loss, net of tax	399					406	406	(7)
Cash dividends	(345)			(345)			(345)
Purchase of treasury stock	(1,000)				(1,000)		(1,000)
Issuance of treasury stock	80		25		55		80
Stock-based compensation activity	58		58				58
Separation and merger tender offer	(90)							(90)
Joint venture formation and consolidation	(18)							(18)
Ending balance at Dec. 31, 2013	5,198	484	953	12,757	(8,002)	(1,260)	4,932	266
Net income attributable to the controlling and noncontrolling interests	2,159			2,102			2,102	57
Other comprehensive loss, net of tax	(862)					(856)	(856)	(6)
Cash dividends	(361)			(361)			(361)
Purchase of treasury stock	(750)				(750)		(750)
Issuance of treasury stock	77		39		38		77
Stock-based compensation activity	64		64				64
Separation and merger tender offer	(50)							(50)
Reductions in noncontrolling interests	(210)		(28)				(28)	(182)
Ending balance at Dec. 31, 2014	5,265	484	1,028	14,498	(8,714)	(2,116)	5,180	85
Net income attributable to the controlling and noncontrolling interests	1,427			1,406			1,406	21
Other comprehensive loss, net of tax	(599)					(586)	(586)	(13)
Cash dividends	(383)			(383)			(383)
Purchase of treasury stock	(751)				(751)		(751)
Issuance of treasury stock	71		46		25		71
Stock-based compensation activity	46		46				46
Separation and merger tender offer	(4)							(4)
Reductions in noncontrolling interests	(3)		0				0	(3)
Ending balance at Dec. 31, 2015	$ 5,069	$ 969	$ 635	$ 15,521	$ (9,440)	$ (2,702)	$ 4,983	$ 86