Condensed Consolidated Statement of Comprehensive Income (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Statement of Comprehensive Income [Abstract]
Net income attributable to the controlling and noncontrolling interests	$ 377	$ 255	$ 2,070	$ 3,071
Other comprehensive (loss) income, net of tax:
Defined benefit pension and other postretirement benefits	16	0	41	198
Unrealized foreign currency translation adjustments	(294)	172	(236)	(18)
Unrealized losses on marketable securities	0	(1)	0	0
Derivative financial instruments	6	2	6	9
Other comprehensive (loss) income, net of tax	(272)	173	(189)	189
Total comprehensive income	105	428	1,881	3,260
Less: amounts attributable to noncontrolling interests:
Net income	(6)	(29)	(51)	(94)
Unrealized foreign currency translation adjustments	6	(3)	2	8
Comprehensive income attributable to PPG	$ 105	$ 396	$ 1,832	$ 3,174