Consolidated Statements of Comprehensive (Loss) Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Statement of Comprehensive Income [Abstract]
Net loss	$ (4,006)	$ (3,361)	$ (1,213)	$ (15,875)
Unrealized gains (losses) on available-for-sale investments:
Unrealized gains (losses) arising during the period	52	(44)	284	(481)
Reclassification adjustment for amounts included in net loss	(6)	6	(19)	(5)
Change in fair value of debt attributable to instrument-specific credit risk	(951)	658	(2,646)	1,002
Equity in other comprehensive income of limited liability investment	0	0	45	0
Other comprehensive (loss) income	(905)	620	(2,336)	516
Comprehensive loss	(4,911)	(2,741)	(3,549)	(15,359)
Less: comprehensive income attributable to noncontrolling interests in consolidated subsidiaries	203	200	684	711
Comprehensive loss attributable to common shareholders	$ (5,114)	$ (2,941)	$ (4,233)	$ (16,070)