Acquisitions (Consolidated Pro Forma Results Of Acquisition) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2014	Mar. 31, 2013
Business Combinations [Abstract]
Revenues	$ 263,107	$ 270,371
Net earnings	60,114	65,385
Amounts Attributable To Common Shareholders
Net earnings from continuing operations	17,504	18,830
Net earnings	$ 17,195	$ 18,891
Net earnings from continuing operations per common share: Basic	$ 0.55	$ 0.6
Net earnings from continuing operations per common share: Diluted	$ 0.54	$ 0.59
Net earnings: Basic	$ 0.54	$ 0.61
Net earnings: Diluted	$ 0.54	$ 0.59
Weighted average number of shares and share equivalents: Basic	31,716	31,217
Weighted average number of shares and share equivalents: Diluted	32,120	31,881

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Net earnings before noncontrolling interest and discontinued operations.

+ References

No definition available.

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- Definition

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (h)(2)-(3)

-URI http://asc.fasb.org/extlink&oid=25497992&loc=d3e1392-128463

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- Definition

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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- Definition

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.

+ References

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- Definition

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.

+ References

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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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- Definition

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.

+ References

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.

+ References

No definition available.

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