Summary of Significant Accounting Policies - Investment in Unconsolidated Investees (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2021 USD ($) Item	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
INVESTMENT IN UNCONSOLIDATED INVESTEES:
Investment amount	$ 171,311	$ 128,382
Investee earnings recorded in income	37,060	20,233	$ 20,960
Reinsurance assumed	34,261	29,129	25,047
Net premiums earned	980,903	865,747	839,111
Undistributed earnings from equity method investees included in retained earnings	145,800
Dividends received		4,675	13,200
Investments in Unconsolidated Investees
INVESTMENT IN UNCONSOLIDATED INVESTEES:
Investee earnings recorded in income	$ 125,300	70,400	77,300
Maui Jim Inc.
INVESTMENT IN UNCONSOLIDATED INVESTEES:
Equity ownership interest (as a percent)	40.00%
Investment amount	$ 113,100	90,900
Investee earnings recorded in income	$ 22,800	10,400	13,600
Dividends received			13,200
Prime Holdings Insurance Services, Inc. (Prime)
INVESTMENT IN UNCONSOLIDATED INVESTEES:
Equity ownership interest (as a percent)	23.00%
Investment amount	$ 47,200	32,700
Investee earnings recorded in income	$ 17,000	10,800	7,400
Number of insurance carriers Company writes through | Item	2
Reinsurance assumed	$ 22,200	15,700	13,100
Net premiums earned	$ 19,100	14,300	$ 28,700
Dividends received		$ 4,700