Consolidated Statement of Income (USD $) In Millions, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Statement [Abstract]
Net sales	$ 15,360	$ 14,265	$ 12,686
Cost of sales, exclusive of depreciation and amortization	8,791	8,314	7,599
Selling, general and administrative	3,758	3,486	2,987
Depreciation	350	333	292
Amortization	126	119	107
Research and development, net	492	463	430
Interest expense	187	196	210
Interest income	(50)	(43)	(40)
Asbestos settlement, net	12	11	12
Business restructuring	0	98	176
Debt refinancing charge	317	0	0
Other charges	221	189	223
Other income	(260)	(127)	(138)
Income before income taxes	1,416	1,226	828
Income tax expense	259	253	148
Income from continuing operations	1,157	973	680
Income from discontinued operations, net of tax	1,002	2,380	384
Net income attributable to the controlling and noncontrolling interests	2,159	3,353	1,064
Less: net income attributable to noncontrolling interests	57	122	123
Net income (attributable to PPG)	2,102	3,231	941
Continuing operations	1,133	950	663
Discontinued operations	$ 969	$ 2,281	$ 278
Earnings per common share
Continuing operations (in dollars per share)	$ 8.19	$ 6.62	$ 4.32
Discontinued operations (in dollars per share)	$ 7.01	$ 15.91	$ 1.81
Net Income (attributable to PPG) (in dollars per share)	$ 15.20	$ 22.53	$ 6.13
Earnings per common share - assuming dilution
Continuing operations (in dollars per share)	$ 8.10	$ 6.55	$ 4.27
Discontinued operations (in dollars per share)	$ 6.93	$ 15.72	$ 1.79
Net Income (attributable to PPG) (in dollars per share)	$ 15.03	$ 22.27	$ 6.06