Condensed Consolidated Statement of Income (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Income Statement [Abstract]
Net sales	$ 3,662	$ 3,636
Cost of sales, exclusive of depreciation and amortization	2,065	2,091
Selling, general and administrative	914	900
Depreciation	87	89
Amortization	33	30
Research and development, net	119	120
Interest expense	29	47
Interest income	(11)	(12)
Asbestos settlement, net	3	3
Other charges	24	21
Other income	(31)	(25)
Income from continuing operations before income taxes	430	372
Income tax expense	104	89
Income from continuing operations	326	283
Income from discontinued operations, net of tax	1	1,018
Net income attributable to the controlling and noncontrolling interests	327	1,301
Less: Net income attributable to noncontrolling interests	(5)	(39)
Net income (attributable to PPG)	322	1,262
Income from continuing operations, net of tax	321	277
Income from discontinued operations, net of tax	$ 1	$ 985
Income from continuing operations, net of tax	$ 2.35	$ 1.99
Income from discontinued operations, net of tax	$ 0.01	$ 7.08
Net income (attributable to PPG)	$ 2.36	$ 9.07
Income from continuing operations, net of tax	$ 2.33	$ 1.97
Income from discontinued operations, net of tax	$ 0.01	$ 7.00
Net income (attributable to PPG)	$ 2.34	$ 8.97
Dividends per common share	$ 0.67	$ 0.61