Amount of cash expected to be paid in future periods for the specified restructuring cost.

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Amount non-cash charges expected to be incurred in future periods for the specified restructuring cost.

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Foreign Currency Translation Adjustment Amount

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Number of Employees Impacted

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Number of Employees Included in Plan Who Ceased Employment in Period

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Amount of Board approved costs related to restructuring program.

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Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

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The expected number of positions to be eliminated as a result of restructuring activities.

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

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Net total Increase or Decrease in the accrual for restructuring costs during the reporting period.

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Business Restructuring (Additional Information) (Detail) (USD $) In Millions, unless otherwise specified	1 Months Ended	12 Months Ended			18 Months Ended
	Mar. 31, 2012	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2014 employee	Jul. 18, 2013
Restructuring Cost and Reserve [Line Items]
Restructuring Program, Approved Cost						$ 98ppg_RestructuringProgramApprovedCost
Restructuring and Related Cost, Expected Number of Positions Eliminated					1,400
Restructuring Reserve, Settled with Cash		57us-gaap_PaymentsForRestructuring	86us-gaap_PaymentsForRestructuring	87us-gaap_PaymentsForRestructuring
Business restructuring	208us-gaap_RestructuringCharges	0us-gaap_RestructuringCharges	98us-gaap_RestructuringCharges	176us-gaap_RestructuringCharges
2013 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve		24	70		24
Expected Non-Cash Charges from Restructuring					5
Restructuring Program, Approved Cost						98
Foreign Currency Translation Adjustment Amount		4	4		4
Expected Cash Charges Related to Restructuring		46			93
Restructuring Reserve, Settled with Cash			27
Business restructuring			98
Number of employees impacted		23	791
Restructuring Reserve, Period Increase (Decrease)		$ (46)	$ (32)
Number Of Employees Included In Plan Who Ceased Employment In Period		768