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Earnings Per Share (Schedule Of Weighted-Average Number Of Shares Outstanding) (Detail) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Weighted Average Number Of Shares Outstanding Reconciliation [Line Items]
Basic weighted average common shares outstanding	92,186	92,060	92,164	92,052
Dilution effect of stock awards at end of period	230	104	179	156
Diluted weighted average common shares outstanding	92,416	92,164	92,343	92,208
Anti-dilutive stock-based compensation awards	748	281	541	174

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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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