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Investments - Narrative (Details) - USD ($) $ in Thousands	Mar. 31, 2025	Dec. 31, 2024
Accrued Investment Income [Line Items]
Accrued investment income	$ 77,110	$ 76,892
5.90% Senior Notes
Accrued Investment Income [Line Items]
Interest rate (as a percent)	5.90%
Debt Securities, Available-For-Sale
Accrued Investment Income [Line Items]
Accrued investment income	$ 74,600	$ 74,300

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Accrued Investment Income

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Interest, dividends, rents, ancillary and other revenues earned but not yet received by the entity on its investments.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
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Contractual interest rate for funds borrowed, under the debt agreement.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
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-Name Accounting Standards Codification
-Section S99
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-Topic 470
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