Equity-Based Compensation (Summary of Stock Option Transactions) (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Options (in shares):
Beginning balance (in shares)	277,224	458,349	569,319
Granted (in shares)	25,000	0	37,500
Exercised (in shares)	(42,058)	(175,125)	(119,096)
Forfeited (in shares)	(12,500)	(6,000)	(29,374)
Ending balance (in shares)	247,666	277,224	458,349
Weighted Average Exercise Price (in dollars per share)
Begininng balance (in dollars per share)	$ 14.95	$ 16.57	$ 15.88
Granted (in dollars per share)	42.35		25.44
Exercised (in dollars per share)	16.02	19.08	15.13
Forfeited (in dollars per share)	25.44	18.22	20.28
Ending balance (in dollars per share)	$ 17.01	$ 14.95	$ 16.57
Weighted Average Remaining Contractual Life (in years)	5 years 3 months 7 days
Aggregate Intrinsic Value	$ 4,194