Consolidated Statements of Comprehensive (Loss) Income - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ (396)	$ (10,296)	$ 2,793	$ (12,514)
Unrealized gains (losses) on available-for-sale investments:
Unrealized gains (losses) arising during the period	121	(72)	232	(437)
Reclassification adjustment for amounts included in net (loss) income	(7)	(4)	(13)	(11)
Change in fair value of debt attributable to instrument-specific credit risk	(750)	778	(1,695)	344
Equity in other comprehensive income of limited liability investment	45	0	45	0
Other comprehensive (loss) income	(591)	702	(1,431)	(104)
Comprehensive (loss) income	(987)	(9,594)	1,362	(12,618)
Less: comprehensive income attributable to noncontrolling interests in consolidated subsidiaries	264	158	481	511
Comprehensive (loss) income attributable to common shareholders	$ (1,251)	$ (9,752)	$ 881	$ (13,129)

Unrealized gains (losses) on fixed maturities and equity investments: [Abstract]

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