Fair Value of Financial Instruments - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Fair Value of Financial Instruments (Textual) [Abstract]
Net investment gains (losses) included in net income related to financial assets	$ 46	$ 0	$ 46	$ (243)
Level 3
Fair Value of Financial Instruments (Textual) [Abstract]
Percentage of invested assets in total investment portfolio Level 3 recurring	4.30%		4.30%
Net realized investment losses	$ (3,661)	$ (2,205)	$ (8,366)	$ (1,308)