Condensed Consolidated Statement of Comprehensive Income - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Statement of Comprehensive Income [Abstract]
Net income attributable to the controlling and noncontrolling interests	$ 439	$ 377	$ 1,108	$ 2,070
Other comprehensive (loss) income, net of tax:
Defined benefit pension and other postretirement benefits	35	16	109	41
Unrealized foreign currency translation adjustments	(300)	(294)	(599)	(236)
Derivative financial instruments, net	2	6	6	6
Other comprehensive loss, net of tax	(263)	(272)	(484)	(189)
Total comprehensive income	176	105	624	1,881
Less: amounts attributable to noncontrolling interests:
Net income	(6)	(6)	(16)	(51)
Unrealized foreign currency translation adjustments	3	6	8	2
Comprehensive income attributable to PPG	$ 173	$ 105	$ 616	$ 1,832