Policy Acquisition Costs - Schedule of Policy Acquisition Costs Deferred and Amortized to Income (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Policy acquisition costs deferred and amortized to income
Deferred policy acquisition costs (DAC), beginning of year	$ 88,425	$ 85,044	$ 84,934
Deferred:
Direct commissions	236,145	200,917	185,164
Premium taxes	17,012	14,783	14,395
Ceding commissions	(47,592)	(42,115)	(31,140)
Net deferred	205,565	173,585	168,419
Amortized	190,437	170,204	168,309
DAC, end of year	103,553	88,425	85,044
Policy acquisition costs:
Amortized	190,437	170,204	168,309
Period costs:
Ceding commission - contingent	(4,303)	(4,053)	(3,034)
Other underwriting expenses	131,334	120,287	123,422
Total policy acquisition costs	$ 317,468	$ 286,438	$ 288,697