Acquisitions (Consolidated Pro Forma Results Of Acquisition) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2012	Mar. 31, 2011
Acquisitions
Revenues	$ 230,770	$ 226,640
Net earnings	55,084	77,219
Amounts Attributable To Common Shareholders
Net earnings from continuing operations	15,771	14,804
Net earnings	$ 14,827	$ 14,497
Net earnings from continuing operations per common share: Basic	$ 0.52	$ 0.49
Net earnings from continuing operations per common share: Diluted	$ 0.50	$ 0.48
Net earnings: Basic	$ 0.48	$ 0.48
Net earnings: Diluted	$ 0.47	$ 0.47
Weighted average number of shares and share equivalents: Basic	30,619	30,420
Weighted average number of shares and share equivalents: Diluted	31,401	31,024

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Net earnings before noncontrolling interest and discontinued operations.

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No definition available.

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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.

+ References

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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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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The pro forma income from continuing operations before changes in accounting and extraordinary items, net of tax effect per basic share of common stock 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 income from continuing operations before changes in accounting and extraordinary items, net of tax effect, per diluted share of common stock 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 income from continuing operations before changes in accounting and extraordinary items, net of tax effect, for the period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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The weighted average number of shares or units and dilutive common stock or unit equivalents outstanding in the calculation of proforma diluted earnings per share (earnings per unit), which is commonly presented in initial public offerings based on the terms of the offering.

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No definition available.

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The weighted average number of shares (units) outstanding in the calculation of pro forma basic earnings per share (earnings per unit), which is commonly presented in initial public offerings based on the terms of the offering.

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