Condensed Consolidated Statement of Comprehensive Income (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Statement of Comprehensive Income [Abstract]
Net income attributable to the controlling and noncontrolling interests	$ 327us-gaap_ProfitLoss	$ 1,301us-gaap_ProfitLoss
Other comprehensive (loss) income, net of tax:
Defined benefit pension and other postretirement benefits	68	11
Unrealized foreign currency translation adjustments	(272)	17
Derivative financial instruments	6	3
Other comprehensive (loss) income, net of tax	(198)	31
Total comprehensive income	129	1,332
Less: amounts attributable to noncontrolling interests:
Net income	(5)	(39)
Unrealized foreign currency translation adjustments	5	(1)
Comprehensive income attributable to PPG	$ 129us-gaap_ComprehensiveIncomeNetOfTax	$ 1,292us-gaap_ComprehensiveIncomeNetOfTax

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount of Net Income (Loss) attributable to noncontrolling interest.

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature, attributable to noncontrolling interests.

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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