Acquisitions (Schedule of Pro Forma) (Details) $ / shares in Units, $ in Thousands	12 Months Ended
Dec. 31, 2014 USD ($) $ / shares
Business Combinations [Abstract]
Business Acquisition, Pro Forma Revenue \| $	$ 2,337,409
Business Acquisition, Pro Forma Income (Loss) from Continuing Operations before Changes in Accounting and Extraordinary Items, Net of Tax \| $	$ 280,869
Business Acquisition, Pro Forma Earnings Per Share, Basic \| $ / shares	$ 3.90
Business Acquisition, Pro Forma Earnings Per Share, Diluted \| $ / shares	$ 3.86

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.

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=56956515&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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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 revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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