Condensed Consolidated Statement of Income (Unaudited) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Income Statement [Abstract]
Net sales	$ 3,826	$ 3,817	$ 11,474	$ 11,729
Cost of sales, exclusive of depreciation and amortization	2,181	2,253	6,542	6,813
Selling, general and administrative	887	867	2,710	2,718
Depreciation	99	89	276	267
Amortization	34	33	101	103
Research and development, net	107	110	323	336
Interest expense	33	31	99	88
Interest income	(10)	(6)	(23)	(18)
Business restructuring, net	2	(12)	175	71
Other charges	26	25	69	72
Other income	(14)	(24)	(61)	(72)
Income before income taxes	481	451	1,263	1,351
Income tax expense	109	79	297	270
Income from continuing operations	372	372	966	1,081
Income from discontinued operations, net of tax	1	10	3	16
Net income attributable to controlling and noncontrolling interests	373	382	969	1,097
Less: Net income attributable to noncontrolling interests	6	4	18	14
Net income (attributable to PPG)	367	378	951	1,083
Income from continuing operations, net of tax	366	368	948	1,067
Income from discontinued operations, net of tax	$ 1	$ 10	$ 3	$ 16
Income from continuing operations, net of tax (in usd per share)	$ 1.55	$ 1.52	$ 4.00	$ 4.34
Income from discontinued operations, net of tax (in usd per share)	0	0.04	0.01	0.07
Net income (attributable to PPG) (in usd per share)	1.55	1.56	4.01	4.41
Income from continuing operations, net of tax (in usd per share)	1.54	1.51	3.98	4.32
Income from discontinued operations, net of tax (in usd per share)	0	0.04	0.01	0.06
Net income (attributable to PPG) (in usd per share)	$ 1.54	$ 1.55	$ 3.99	$ 4.38