Condensed Consolidated Balance Sheets (Parenthetical) (USD $) In Millions, except Share data, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Condensed Consolidated Balance Sheets
Property, plant and equipment - net of accumulated depreciation (in dollars)	$ 2,759	$ 2,813
Other intangible assets - net of accumulated amortization (in dollars)	$ 65	$ 62
Preferred stock, authorized shares	25,000,000us-gaap_PreferredStockSharesAuthorized	25,000,000us-gaap_PreferredStockSharesAuthorized
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, issued shares	0us-gaap_PreferredStockSharesIssued	0us-gaap_PreferredStockSharesIssued
Common stock, authorized shares	200,000,000us-gaap_CommonStockSharesAuthorized	200,000,000us-gaap_CommonStockSharesAuthorized
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares issued	77,810,875us-gaap_CommonStockSharesIssued	77,810,875us-gaap_CommonStockSharesIssued
Treasury stock, shares	6,494,373us-gaap_TreasuryStockShares	6,488,605us-gaap_TreasuryStockShares

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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