Acquisitions (Consolidated Pro Forma Results Of Acquisition) (Details) (USD $) In Thousands, except Per Share data	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010
Acquisitions
Revenues	$ 648,490	$ 648,788
Net earnings	151,327	160,298
Amounts Attributable To Common Shareholders
Net earnings from continuing operations	41,644	46,761
Net earnings	$ 40,591	$ 47,750
Net earnings from continuing operations per common share: Basic	$ 1.37	$ 1.55
Net earnings from continuing operations per common share: Diluted	$ 1.34	$ 1.52
Net earnings: Basic	$ 1.33	$ 1.58
Net earnings: Diluted	$ 1.30	$ 1.56
Weighted average number of shares and share equivalents: Basic	30,424	30,234
Weighted average number of shares and share equivalents: Diluted	31,174	30,664

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Net earnings before noncontrolling interest and discontinued operations.

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The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

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