Revenue (Impact on Balance Sheet) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Jan. 01, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Other assets	$ 33,324		$ 8,291
Total assets	1,785,153		1,651,983
Deferred tax assets, net	1,482		10,143
Retained earnings	105,642		72,741
Total stockholders’ equity	665,141		$ 612,250	$ 397,642	$ 336,969
Adjustments | ASU 2014-09
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Other assets	(8,776)
Total assets	(8,776)	$ 9,300
Deferred tax assets, net	2,198
Retained earnings	6,578	$ 6,900
Total stockholders’ equity	6,578
Balance without adoption of ASC 606
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Other assets	24,548
Total assets	1,776,377
Deferred tax assets, net	3,680
Retained earnings	99,064
Total stockholders’ equity	$ 658,563