Consolidated Statement of Income - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Statement [Abstract]
Net sales	$ 14,750	$ 14,270	$ 14,241
Cost of sales, exclusive of depreciation and amortization	8,204	7,693	7,786
Selling, general and administrative	3,570	3,581	3,584
Depreciation	331	319	314
Amortization	129	121	132
Research and development, net	453	459	466
Interest expense	105	125	125
Interest income	(20)	(26)	(39)
Asbestos settlement, net	0	5	12
Business restructuring	0	195	136
Pension Settlement Charges	60	968	0
Other charges	64	175	90
Other income	(154)	(131)	(110)
Income before income taxes	2,008	786	1,745
Income tax expense	616	217	413
Income from continuing operations	1,392	569	1,332
Income from discontinued operations, net of tax	220	330	95
Net income attributable to the controlling and noncontrolling interests	1,612	899	1,427
Less: net income attributable to noncontrolling interests	21	22	21
Net income (attributable to PPG)	1,591	877	1,406
Continuing operations	1,371	547	1,311
Discontinued operations	$ 220	$ 330	$ 95
Earnings per common share
Continuing operations (in dollars per share)	$ 5.35	$ 2.06	$ 4.83
Discontinued operations (in dollars per share)	0.86	1.24	0.35
Net Income (attributable to PPG) (in dollars per share)	6.21	3.30	5.18
Earnings per common share - assuming dilution
Continuing operations (in dollars per share)	5.32	2.05	4.79
Discontinued operations (in dollars per share)	0.85	1.23	0.35
Net Income (attributable to PPG) (in dollars per share)	$ 6.17	$ 3.28	$ 5.14