Acquisitions (Consolidated Pro Forma Results Of Acquisition) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	6 Months Ended
Jun. 30, 2013	Jun. 30, 2012
Acquisitions
Revenues	$ 532,920	$ 543,297
Net earnings	129,277	131,257
Amounts Attributable To Common Shareholders
Net earnings from continuing operations	36,694	36,730
Net earnings	$ 36,694	$ 35,826
Net earnings from continuing operations per common share: Basic	$ 1.18	$ 1.20
Net earnings from continuing operations per common share: Diluted	$ 1.15	$ 1.17
Net earnings: Basic	$ 1.18	$ 1.17
Net earnings: Diluted	$ 1.15	$ 1.14
Weighted average number of shares and share equivalents: Basic	31,213	30,681
Weighted average number of shares and share equivalents: Diluted	31,872	31,489

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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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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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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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