Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Statement of Comprehensive Income [Abstract]
Net income	$ 19,224	$ 15,865	$ 30,244
Change in net unrealized loss on investments, net of tax	(57)	(202)	0
Less: reclassification adjustment for net realized gain (loss) included in net income, net of tax	112	(19)	(28)
Net change	55	(221)	(28)
Other comprehensive income (loss), net	55	(221)	(28)
Comprehensive income	$ 19,279	$ 15,644	$ 30,216