Condensed Consolidated Statement of Income - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Income Statement [Abstract]
Net sales	$ 4,131	$ 3,804	$ 7,912	$ 7,290
Cost of sales, exclusive of depreciation and amortization	2,379	2,083	4,560	3,985
Selling, general and administrative	945	876	1,851	1,751
Depreciation	91	81	178	160
Amortization	34	32	70	63
Research and development, net	114	112	226	221
Interest expense	31	26	57	51
Interest income	(7)	(4)	(12)	(8)
Pension settlement charge	0	0	0	22
Business restructuring charge	83	0	83	0
Other charges	6	8	47	33
Other income	(24)	(69)	(48)	(93)
Income from continuing operations before income taxes	479	659	900	1,105
Income tax expense	104	157	191	267
Income from continuing operations	375	502	709	838
(Loss)/Income from discontinued operations, net of tax	0	(1)	6	5
Net income attributable to controlling and noncontrolling interests	375	501	715	843
Less: Net income attributable to noncontrolling interests	4	5	10	10
Net income (attributable to PPG)	371	496	705	833
Income from continuing operations, net of tax	371	497	699	828
(Loss)/Income from discontinued operations, net of tax	$ 0	$ (1)	$ 6	$ 5
Income from continuing operations, net of tax (in usd per share)	$ 1.51	$ 1.93	$ 2.83	$ 3.22
Income from discontinued operations, net of tax (in usd per share)	0.00	0.00	0.02	0.02
Net income (attributable to PPG) (in usd per share)	1.51	1.93	2.85	3.24
Income from continuing operations, net of tax (in usd per share)	1.51	1.92	2.81	3.19
Income from discontinued operations, net of tax (in usd per share)	0.00	0.00	0.02	0.02
Net income (attributable to PPG) (in usd per share)	1.51	1.92	2.83	3.21
Dividends per common share (in usd per share)	$ 0.45	$ 0.40	$ 0.90	$ 0.80