Shareholders' Equity (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance			$ 5,265	$ 5,198
Net income	$ 439	$ 377	1,108	2,070
Other comprehensive income, net of tax	(263)	(272)	(484)	(189)
Cash dividends			(287)	(269)
Issuance of treasury stock			69	64
Purchase of treasury stock			(501)	(450)
Stock-based compensation activity			34	40
Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests			(5)	(211)
Dividends paid on subsidiary common stock to noncontrolling interests			(3)	(48)
Ending balance	5,196	6,205	5,196	6,205
Total PPG Shareholders' Equity [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance			5,180	4,932
Net income			1,092	2,019
Other comprehensive income, net of tax			(476)	(187)
Cash dividends			(287)	(269)
Issuance of treasury stock			69	64
Purchase of treasury stock			(501)	(450)
Stock-based compensation activity			34	40
Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests			0	(28)
Dividends paid on subsidiary common stock to noncontrolling interests			0	0
Ending balance	5,111	6,121	5,111	6,121
Non-controlling Interests [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance			85	266
Net income			16	51
Other comprehensive income, net of tax			(8)	(2)
Cash dividends			0	0
Issuance of treasury stock			0	0
Purchase of treasury stock			0	0
Stock-based compensation activity			0	0
Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests			(5)	(183)
Dividends paid on subsidiary common stock to noncontrolling interests			(3)	(48)
Ending balance	$ 85	$ 84	$ 85	$ 84