Condensed Consolidated Statement of Income (Unaudited) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Income Statement [Abstract]
Net sales	$ 4,308	$ 3,881
Cost of sales, exclusive of depreciation and amortization	2,698	2,232
Selling, general and administrative	974	891
Depreciation	102	90
Amortization	43	39
Research and development, net	115	102
Interest expense	30	30
Interest income	(9)	(6)
Impairment and other related charges	290	0
Other charges	13	17
Other income	(26)	(13)
Income before income taxes	78	499
Income tax expense	55	114
Net income attributable to the controlling and noncontrolling interests	23	385
Net income attributable to noncontrolling interests	5	7
Net income (attributable to PPG)	$ 18	$ 378
Earnings per common share (attributable to PPG) (in dollars per share)	$ 0.08	$ 1.59
Earnings per common share (attributable to PPG) - assuming dilution (in dollars per share)	$ 0.08	$ 1.58