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Earnings Per Share (Schedule Of Weighted-Average Number Of Shares Outstanding) (Detail) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Weighted Average Number Of Shares Outstanding Reconciliation [Line Items]
Basic weighted average common shares outstanding	92,176	92,048	92,153	92,047
Dilution effect of stock awards at end of period	46	103	186	130
Diluted weighted average common shares outstanding	92,222	92,151	92,339	92,177
Anti-dilutive stock-based compensation awards	634	272	397	173

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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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