Other Comprehensive Income (Loss) - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Other Comprehensive Income (Loss), Net of Tax [Abstract]
Net realized investment gains (losses)	$ 1,081	$ (554)	$ (835)
Bank loan participations realized investment gains (losses)	(10,056)	1,113	(1,150)
Changes in fair values of equity securities	$ 6,257	$ (5,970)	$ 0

Amount before tax of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

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