Summary of Significant Accounting Policies - Investment in Unconsolidated Investees (Details) $ in Thousands	12 Months Ended
Dec. 31, 2023 USD ($) item	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Sep. 29, 2022
INVESTMENT IN UNCONSOLIDATED INVESTEES:
Investment in unconsolidated investees	$ 56,966	$ 58,275
Investee earnings recorded in income	9,610	9,853	$ 37,060
Reinsurance assumed	22,798	33,830	34,261
Net premiums earned	1,294,306	1,144,436	980,903
Undistributed earnings from equity method investees included in retained earnings	62,000
Dividends received	$ 0	0	$ 0
Maui Jim Inc.
INVESTMENT IN UNCONSOLIDATED INVESTEES:
Equity ownership interest (as a percent)			40.00%	40.00%
Investee earnings recorded in income			$ 23,000
Maui Jim Inc. \| Maximum
INVESTMENT IN UNCONSOLIDATED INVESTEES:
Investee earnings recorded in income		1,000
Prime Holdings Insurance Services, Inc. (Prime)
INVESTMENT IN UNCONSOLIDATED INVESTEES:
Equity ownership interest (as a percent)	23.00%
Investment in unconsolidated investees	$ 56,000	47,000
Investee earnings recorded in income	$ 10,000	13,000	17,000
Number of insurance carriers Company writes through \| item	2
Reinsurance assumed	$ 7,000	21,000	22,000
Net premiums earned	$ 13,000	$ 23,000	$ 19,000

Number of insurance carriers the Company writes business through.

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