Acquisitions and Dispositions (Net Sales and Earnings from Discontinued Operations) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net gain from divestiture of PPG's interest in the Transitions Optical joint venture and sunlens business		$ 1,468
Income from discontinued operations, net of tax	1	1,018
Less: Net income attributable to non-controlling interests, discontinued operations	5	39
Net income from discontinued operations (attributable to PPG)	1	985
Transitions Optical Business [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net sales	0	247
Income from operations	0	104
Net gain from divestiture of PPG's interest in the Transitions Optical joint venture and sunlens business	0	1,468
Income tax benefit (expense)	1	(554)
Income from discontinued operations, net of tax	1	1,018
Less: Net income attributable to non-controlling interests, discontinued operations	0	(33)
Net income from discontinued operations (attributable to PPG)	$ 1	$ 985