Condensed Consolidated Statement of Income (Unaudited) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Income Statement [Abstract]
Net sales	$ 4,024	$ 4,131	$ 7,648	$ 7,912
Cost of sales, exclusive of depreciation and amortization	2,288	2,379	4,361	4,560
Selling, general and administrative	934	945	1,823	1,851
Depreciation	91	91	177	178
Amortization	35	34	67	70
Research and development, net	111	114	216	226
Interest expense	35	31	66	57
Interest income	(7)	(7)	(13)	(12)
Business restructuring, net	176	83	173	83
Other charges	29	6	43	47
Other income	(31)	(24)	(47)	(48)
Income before income taxes	363	479	782	900
Income tax expense	86	104	188	191
Income from continuing operations	277	375	594	709
Income from discontinued operations, net of tax	2	0	2	6
Net income attributable to controlling and noncontrolling interests	279	375	596	715
Less: Net income attributable to noncontrolling interests	7	4	12	10
Net income (attributable to PPG)	272	371	584	705
Income from continuing operations, net of tax	270	371	582	699
Income from discontinued operations, net of tax	$ 2	$ 0	$ 2	$ 6
Income from continuing operations, net of tax (in usd per share)	$ 1.14	$ 1.51	$ 2.46	$ 2.83
Income from discontinued operations, net of tax (in usd per share)	0.01	0	0.01	0.02
Net income (attributable to PPG) (in usd per share)	1.15	1.51	2.47	2.85
Income from continuing operations, net of tax (in usd per share)	1.13	1.51	2.44	2.81
Income from discontinued operations, net of tax (in usd per share)	0.01	0	0.01	0.02
Net income (attributable to PPG) (in usd per share)	$ 1.14	$ 1.51	$ 2.45	$ 2.83