Summary of Significant Accounting Policies - Investment in Unconsolidated Investees (Details) $ in Thousands	12 Months Ended
Dec. 31, 2022 USD ($) item	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Sep. 29, 2022
INVESTMENT IN UNCONSOLIDATED INVESTEES:
Investment in unconsolidated investees	$ 58,275	$ 171,311
Investee earnings recorded in income	9,853	37,060	$ 20,233
Reinsurance assumed	33,830	34,261	29,129
Net premiums earned	1,144,436	980,903	865,747
Undistributed earnings from equity method investees included in retained earnings	51,600
Dividends received	0	$ 0	4,675
Maui Jim Inc.
INVESTMENT IN UNCONSOLIDATED INVESTEES:
Equity ownership interest (as a percent)		40.00%		40.00%
Investment in unconsolidated investees		$ 113,100
Investee earnings recorded in income	$ 400	22,800	10,400
Prime Holdings Insurance Services, Inc. (Prime)
INVESTMENT IN UNCONSOLIDATED INVESTEES:
Equity ownership interest (as a percent)	23.00%
Investment in unconsolidated investees	$ 46,900	47,200
Investee earnings recorded in income	$ 13,000	17,000	10,800
Number of insurance carriers Company writes through \| item	2
Reinsurance assumed	$ 20,600	22,200	15,700
Net premiums earned	$ 22,600	$ 19,100	14,300
Dividends received			$ 4,700

Number of insurance carriers the Company writes business through.

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