Acquisitions (Consolidated Pro Forma Results Of Acquisition) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Business Combinations [Abstract]
Revenues			$ 552,154	$ 558,165
Net earnings			129,720	136,524
Amounts Attributable To Common Shareholders
Net earnings from continuing operations			36,912	38,967
Net earnings			$ 36,610	$ 39,174
Net earnings from continuing operations per common share: Basic (usd per share)			$ 1.16	$ 1.25
Net earnings from continuing operations per common share: Diluted (usd per share)			$ 1.15	$ 1.22
Net earnings: Basic (usd per share)			$ 1.15	$ 1.26
Net earnings: Diluted (usd per share)			$ 1.14	$ 1.23
Weighted average number of shares and share equivalents: Basic (shares)	31,825	31,208	31,770	31,213
Weighted average number of shares and share equivalents: Diluted (shares)	32,233	31,862	32,177	31,872

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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)

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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.

+ References

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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 average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 260

-SubTopic 10

-Section 50

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