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Condensed Financial Information of Registrant Condensed Financial Information of Registrant (Narratives) (Details)			12 Months Ended
	Feb. 11, 2025 USD ($)	Nov. 22, 2024	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Nov. 30, 2023 USD ($)	Nov. 18, 2022 USD ($)	Mar. 31, 2021 USD ($)	Mar. 08, 2017 USD ($)
Condensed Financial Statements, Captions [Line Items]
Capital distribution from subsidiaries			$ 300,000	$ 6,200,000	$ 2,900,000
Proceeds from dividends received			100,000,000	0	0
Payments for contributions to subsidiaries					0
Unsecured Notes One | Level 2 | Notes payable | Unsecured notes
Condensed Financial Statements, Captions [Line Items]
Unsecured debt			$ 375,000,000	375,000,000					$ 375,000,000
Interest rate (in percent)			4.40%						4.40%
Debt issuance costs									$ 3,400,000
Discount percent									99.847%
Interest rate, effective percentage									4.45%
Unsecured Notes Two | Revolving Credit Facility
Condensed Financial Statements, Captions [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity						$ 250,000,000	$ 200,000,000	$ 75,000,000
Drawn down amount under credit facility			$ 200,000,000	200,000,000
Unsecured Notes Two | Revolving Credit Facility | Consolidated Insurance Subsidiary
Condensed Financial Statements, Captions [Line Items]
Drawn down amount under credit facility contributed			$ 150,000,000
Unsecured Notes Two | Revolving Credit Facility | Subsequent Event
Condensed Financial Statements, Captions [Line Items]
Interest rate, effective percentage	5.79%
Drawn down amount under credit facility	$ 200,000,000
Undrawn portion of credit facility	$ 50,000,000
Unsecured Notes Two | Revolving Credit Facility | Minimum
Condensed Financial Statements, Captions [Line Items]
Debt to total capital ratio		0.20
Commitment fee on undrawn portion of facility		0.125%	0.15%
Unsecured Notes Two | Revolving Credit Facility | Maximum
Condensed Financial Statements, Captions [Line Items]
Debt to total capital ratio		0.30	0.228
Commitment fee on undrawn portion of facility		0.225%
Unsecured Notes Two | Level 2 | Notes payable | Unsecured notes
Condensed Financial Statements, Captions [Line Items]
Unsecured debt			$ 200,000,000	200,000,000
Unsecured Notes Two | Level 2 | Notes payable | Unsecured notes | Minimum
Condensed Financial Statements, Captions [Line Items]
Basis spread on variable rate			1.125%
Unsecured Notes Two | Level 2 | Notes payable | Unsecured notes | Maximum
Condensed Financial Statements, Captions [Line Items]
Basis spread on variable rate			1.50%
Parent Company
Condensed Financial Statements, Captions [Line Items]
Capital distribution from subsidiaries			$ 0	0	3,431,433
Payments for contributions to subsidiaries			$ 165,000	$ 150,000,000	$ 0

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