Condensed Consolidated Statement of Comprehensive Income/(Loss) (Unaudited) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Statement of Comprehensive Income [Abstract]
Net income attributable to controlling and noncontrolling interests	$ 23	$ 385
Other comprehensive income/(loss), net of tax:
Defined benefit pension and other postretirement benefits	(4)	(5)
Unrealized foreign currency translation adjustments	37	(128)
Other comprehensive income/(loss), net of tax	33	(133)
Total comprehensive income	56	252
Less: amounts attributable to noncontrolling interests:
Net income	(5)	(7)
Unrealized foreign currency translation adjustments	3	2
Comprehensive income attributable to PPG	$ 54	$ 247