Schedule II. Condensed Financial Information of Registrant - Condensed Statements of Cash Flows (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Operating activities
Net cash provided by operating activities	$ 11,070	$ 24,190	$ 29,842
Investing activities
Purchases of property and equipment	(2,148)	(840)	(553)
Net cash provided by investing activities	68,423	72,371	43,884
Financing activities
Finance lease purchases	(85)	(85)	(91)
Share-based compensation related tax withholding	(817)	(554)	(944)
Purchase of treasury stock	(12,103)	(5,123)	(2,171)
Dividends to shareholders	(48,607)	(85,436)	(93,307)
Net cash used in financing activities	(61,612)	(91,198)	(96,513)
Change in cash and cash equivalents	17,881	5,363	(22,787)
Cash and cash equivalents at beginning of year	44,045	38,682	61,469
Cash and cash equivalents at end of year	61,926	44,045	38,682
Parent Company [Member]
Operating activities
Net cash provided by operating activities	554	2,623	5,591
Investing activities
Purchases of investments	(4,588)	0	(24,885)
Proceeds from sales of investments	12,223	22,502	35,013
Purchases of property and equipment	(1,124)	231	(482)
Dividends from subsidiary	62,700	71,000	56,000
Net cash provided by investing activities	69,211	93,733	65,646
Financing activities
Finance lease purchases	(85)	(85)	(91)
Share-based compensation related tax withholding	(817)	(554)	(944)
Purchase of treasury stock	(12,103)	(5,123)	(2,171)
Dividends to shareholders	(48,607)	(85,436)	(93,307)
Net cash used in financing activities	(61,612)	(91,198)	(96,513)
Change in cash and cash equivalents	8,153	5,158	(25,276)
Cash and cash equivalents at beginning of year	11,793	6,635	31,911
Cash and cash equivalents at end of year	$ 19,946	$ 11,793	$ 6,635