Business Combinations (Pro Forma Financial Information) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Business Combinations [Abstract]
Revenue	$ 185,485	$ 187,089	$ 340,029	$ 349,893
Net income	$ 25,775	$ 28,403	$ 43,825	$ 28,373
Basic earnings per share	$ 0.24	$ 0.26	$ 0.41	$ 0.25
Diluted earnings per share	$ 0.23	$ 0.26	$ 0.40	$ 0.25

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=79982066&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.

+ References

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- Definition

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.

+ References

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- Definition

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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- References

No definition available.

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