Deferred Policy Acquisition Costs (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Movement Analysis of Deferred Policy Acquisition Costs [Roll Forward]
Balance at beginning of period	$ 54,450	$ 72,365	$ 64,789
Policy acquisition costs deferred:
Commissions	67,303	72,473	107,387
Underwriting and other issue expenses	24,146	20,715	16,190
Policy acquisition costs deferred	91,449	93,188	123,577
Amortization of policy acquisition costs	(83,893)	(111,103)	(116,001)
Net change	7,556	(17,915)	7,576
Balance at end of period	$ 62,006	$ 54,450	$ 72,365