Unaudited Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 1,455	$ (1,913)
Other comprehensive income (loss):
Unrealized (loss) gain on available-for-sale securities	(302)	38
Unrealized gain on interest rate swap	1,328	374
Other comprehensive income before taxes	1,026	412
Provision from income taxes related to other comprehensive income (loss) items	(216)	(162)
Other comprehensive income	810	250
Comprehensive income (loss)	2,265	(1,663)
Comprehensive loss attributable to non-controlling interests	(2)	(11)
Comprehensive income (loss) attributable to common stockholders	$ 2,267	$ (1,652)