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Earnings (Loss) Per Share - Schedule of Weighted-Average Number of Shares Outstanding (Detail) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012		Dec. 31, 2011		Dec. 31, 2010
Reconciliation Of Basic Weighted Average Shares To Diluted Weighted Average Shares [Line Items]
Basic weighted average common shares outstanding	92,180	[1]	92,056	[1]	92,000	[1]
Dilution effect of stock awards at end of period	333		185
Diluted weighted average common shares outstanding	92,513	[1]	92,241	[1]	92,000	[1]
Anti-dilutive stock-based compensation awards	465		160		227
[1] 2010 restated (see Note 11).

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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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The sum of dilutive potential common shares or units used in the calculation of the diluted per-share or per-unit computation.

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