Condensed Consolidated Balance Sheets (Parenthetical) (USD $)	Mar. 31, 2015	Dec. 31, 2014
Stockholders' deficiency:
Preferred stock, par value (in dollars per share)	$ 1.00	$ 1.00
Preferred stock, shares authorized (in shares)	10,000,000us-gaap_PreferredStockSharesAuthorized	10,000,000us-gaap_PreferredStockSharesAuthorized
Common stock, par value (in dollars per share)	$ 0.10	$ 0.10
Common stock, shares authorized (in shares)	250,000,000us-gaap_CommonStockSharesAuthorized	250,000,000us-gaap_CommonStockSharesAuthorized
Common stock, shares issued (in shares)	120,943,959us-gaap_CommonStockSharesIssued	118,646,261us-gaap_CommonStockSharesIssued
Common stock, shares outstanding (in shares)	116,798,712us-gaap_CommonStockSharesOutstanding	114,501,014us-gaap_CommonStockSharesOutstanding
Common stock in treasury, shares (in shares)	4,145,247us-gaap_TreasuryStockShares	4,415,247us-gaap_TreasuryStockShares

Face amount or stated value per share of common stock.

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