Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Operating activities
Net income	$ 62,108	$ 55,602	$ 65,756
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	1,427	1,309	1,017
Net amortization of investments	3,025	6,734	8,868
Change in investment related allowance for credit losses	(57)	44	(79)
Deferred income taxes	628	(1,136)	1,270
Net realized gains on investments	(6,579)	(3,440)	(1,695)
Net unrealized (gains) losses on equity securities	(1,228)	8,092	(12,315)
Net realized (gains) losses on disposal of assets	2	9	(21)
Share-based compensation	1,557	2,479	2,320
Changes in operating assets and liabilities:
Premiums receivable, net	(8,485)	13,387	21,660
Accrued interest receivable	154	(348)	1,194
Deferred policy acquisition costs	(574)	(342)	751
Amounts held by others			71
Other assets	(1,033)	(2,840)	(1,016)
Reserves for loss and loss adjustment expenses	(22,043)	(49,241)	(15,283)
Unearned premiums	1,609	(6,116)	(8,168)
Reinsurance balances	(3,740)	(4,754)	(14,648)
Amounts held for others and policyholder deposits	3,093	2,825	(2,628)
Federal income taxes recoverable	(328)	4,961	(6,831)
Accounts payable and other liabilities	306	969	(2,244)
Net cash provided by operating activities	29,842	28,194	37,979
Investing activities
Purchases of investments held-to-maturity	(42,190)	(32,152)	(43,307)
Purchases of investments available-for-sale	(45,141)	(106,049)	(51,617)
Purchases of equity securities		(11,147)	(8,388)
Purchases of short-term investments	(46,347)	(66,132)	(167,870)
Proceeds from maturities of investments held-to-maturity	47,151	85,006	74,253
Proceeds from sales and maturities of investments available-for-sale	57,153	90,675	114,974
Proceeds from sales of equity securities	12,688	8,487
Proceeds from sales and maturities of short-term investments	61,123	108,827	154,187
Purchases of property and equipment	(553)	(2,089)	(1,296)
Proceeds from sales of property and equipment			23
Net cash provided by investing activities	43,884	75,426	70,959
Financing activities
Finance lease purchases	(91)	(58)	(44)
Share-based compensation related tax withholding	(944)
Purchase of treasury stock	(2,171)	(12,388)
Dividends to shareholders	(93,307)	(100,427)	(99,929)
Net cash used in financing activities	(96,513)	(112,873)	(99,973)
Change in cash and cash equivalents	(22,787)	(9,253)	8,965
Cash and cash equivalents at beginning of year	61,469	70,722	61,757
Cash and cash equivalents at end of year	38,682	61,469	70,722
Supplemental disclosure of cash flow information
Income taxes paid	$ 13,950	$ 7,791	$ 18,198