Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Statement of Comprehensive Income [Abstract]
Consolidated net income	$ 7,044	$ 14,289	$ 10,546	$ 16,380
Other comprehensive (loss) income, before income tax:
Unrealized foreign currency translation (loss) gain	(15)	15	43	(12)
Other comprehensive (loss) income, net of tax	(15)	15	43	(12)
Comprehensive income	7,029	14,304	10,589	16,368
Less: Net income attributable to noncontrolling interest in subsidiary	321	223	983	529
Comprehensive income attributable to common shareholders	$ 6,708	$ 14,081	$ 9,606	$ 15,839