Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

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Derivative Instruments and Hedging Activities Disclosure [Line Items]

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Fair Value of Debt Instrument Designated as a Hedge of Net Investment in Foreign Operations

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Forward Contract Indexed to Issuers Equity, Fair Value

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Forward Contract Indexed to Issuers Equity, Shares, Principal Amount

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Face (par) amount of debt instrument at time of issuance.

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Fair value portion of asset contracts related to the exchange of different currencies, including, but not limited to, foreign currency options, forward contracts, and swaps.

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The number of issuer's shares to which the forward contract is indexed.

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Amount of increase (decrease) in fair value adjustment on other assets (liabilities) carried at fair value under the fair value option on the statement of cash flows of Federal Home Loan Banks (FHLBanks).

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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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Net fair value of all derivatives designated as hedges of net investment in foreign operations.

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Nominal or face amount used to calculate payments on a nonderivative instrument.

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Amount of unrealized gain (loss) related to the increase or decrease in fair value of interest rate derivatives designated as cash flow hedging instruments, which was recorded in accumulated other comprehensive income to the extent that the cash flow hedge was determined to be effective.

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Financial Instruments, Hedging Activities and Fair Value Measurements (Additional Information) (Details) € in Millions	3 Months Ended	6 Months Ended		12 Months Ended
	Mar. 31, 2015 EUR (€)	Jun. 30, 2015 USD ($) shares	Jun. 30, 2015 EUR (€)	Dec. 31, 2014 USD ($)	Dec. 31, 2014 EUR (€)	Mar. 31, 2015 USD ($)	Mar. 31, 2015 EUR (€)	Dec. 31, 2008 USD ($)
Derivative Instruments and Hedging Activities Disclosure [Line Items]
Shares of PPG stock that are to be contributed to the asbestos settlement trust \| shares		1,388,889
Total principal amount payable for PPG shares contributed to the asbestos settlement		$ 62,000,000
Fair value of the equity forward arrangement to mitigate the impact of changes in fair value of stock contributed to the asbestos settlement trust		267,000,000		$ 268,000,000
Fair value of foreign currency forward contracts designated as cash flow hedges, net asset		30,000,000		46,000,000
Notional amount								$ 560,000,000
Fair value of nine U.S. dollar to euro cross currency swap contracts		45,000,000		(32,000,000)
Debt Instrument, Face Amount						$ 1,260,000,000	€ 1,200
Euro-denominated borrowings hedging a portion of PPG's net investment in European operations \| €	€ 300		€ 300
Fair Value of Debt Instrument Designated as a Hedge of Net Investment in Foreign Operations		2,100,000,000		1,200,000,000
Accumulated pretax unrealized translation gains (losses) in AOCI, related to both the euro-denominated borrowings and the cross currency swaps that have been designated as hedges of net investments		(282,000,000)		(169,000,000)
Long-term Debt		4,449,000,000		3,877,000,000
Long-lived assets fair value amount		4,564,000,000		4,164,000,000
Significant Fair Value Adjustments on Other Assets (Liabilities) Carried at Fair Value				$ 0
Settlement Date 15 March 2018
Derivative Instruments and Hedging Activities Disclosure [Line Items]
Notional amount		$ 560,000,000
Net Investment Hedging [Member]
Derivative Instruments and Hedging Activities Disclosure [Line Items]
Euro-denominated borrowings hedging a portion of PPG's net investment in European operations \| €			€ 1,900		€ 1,000