Reinsurance - Allowance for Credit Loss on Reinsurance Recoverable (Details) - USD ($) $ in Thousands		3 Months Ended	6 Months Ended
		Jun. 30, 2020	Jun. 30, 2020
Reinsurance Disclosures [Abstract]
Balance, beginning of period	[1]	$ 5,542	$ 3,917
Current period provision for expected credit losses		60	1,685
Balance, at the end of period		$ 5,602	$ 5,602

[1] The beginning balance for the six months ended June 30, 2020 reflects the adjustment made to the allowance for credit losses balance for the adoption of ASC 326 on January 1, 2020