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Investments (Narrative) (Details) $ in Thousands	3 Months Ended
Investments (Narrative) (Details) $ in Thousands	Mar. 31, 2026 USD ($) business investment issuer security	Mar. 31, 2025 USD ($) bond	Dec. 31, 2025 USD ($) issuer security business
Debt Securities, Available-for-Sale [Line Items]
Number of investment in any entity or affiliates greater than 10% of stockholders' equity \| investment	0
Threshold limit of investments based on shareholders' equity	10.00%
Securities on deposit with state insurance departments	$ 52,100
Number of LPs / LLCs with investment ownership percent over 25% (in businesses) \| business	5		5
Investment in unconsolidated subsidiaries	$ 240,411		$ 245,472
Net impairment losses recognized in earnings	(7)	$ 257
Number of corporate bonds \| bond		4
Tax Year 2019
Debt Securities, Available-for-Sale [Line Items]
Tax credit carryforwards, expected recapture	900
Tax Year 2039
Debt Securities, Available-for-Sale [Line Items]
Tax credit carryforwards	$ 34,700
Other Limited Partnerships and Limited Liability Company, Greater Than 25% Ownership
Debt Securities, Available-for-Sale [Line Items]
Investment ownership percentage	25.00%		25.00%
Investment in unconsolidated subsidiaries	$ 29,000		$ 29,000
Other Limited Partnerships and Limited Liability Company Less than 25% Ownership
Debt Securities, Available-for-Sale [Line Items]
Investment in unconsolidated subsidiaries	$ 211,400		$ 216,400
Maximum \| Tax Credit Partnerships Less Than 20% Ownership
Debt Securities, Available-for-Sale [Line Items]
Investment ownership percentage	20.00%		20.00%
Non government-backed
Debt Securities, Available-for-Sale [Line Items]
Debt securities in unrealized loss position (in securities) \| security	2,098		1,824
Debt securities in unrealized loss position as percentage of total debt securities held	51.50%		45.00%
Issuers in unrealized loss position (in issuers) \| issuer	1,177		1,066
Single greatest unrealized loss position	$ 4,300		$ 4,100
Second greatest unrealized loss position	2,700		$ 2,500
Lloyd's Syndicates
Debt Securities, Available-for-Sale [Line Items]
Required FAL deposit	15,200
Asset Pledged as Collateral
Debt Securities, Available-for-Sale [Line Items]
Securities on deposit with state insurance departments	$ 49,300