Acquisitions - Pro Forma Information (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015
Business Combinations [Abstract]
Revenue	$ 603,673	$ 547,381
Earnings	$ 15,776	$ 15,460

Combination of Entities under Common Control, Pro Forma Net Income (Loss)

No definition available.

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