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Statutory Balances and Accounting Practices - Schedule Of Statutory Net Income And Capital And Surplus (Details) $ in Thousands		12 Months Ended
		Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Statutory Balances And Accounting Practices [Abstract]
Statutory net (loss) income	[1]	$ 446,405	$ (35,590)	$ (184,292)
Statutory capital and surplus		$ 2,030,460	$ 1,667,187	$ 1,502,424
RBC authorized control level		3.50	3.50	3.30
RBC threshold for regulatory or company action		200.00%
[1] Statutory net income (loss) reflects differences from GAAP net income (loss), including changes in the fair value of the investment portfolio as a result of the application of the fair value option.

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- Definition

Risk Based Capital Ratio

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No definition available.

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- Definition

Risk Based Capital Ratio, Threshold For Regulatory Or Company Action

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- Definition

Statutory Balances And Accounting Practices [Abstract]

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- Definition

The amount of statutory capital and surplus (stockholders' equity) as of the balance sheet date using prescribed or permitted statutory accounting practices (rather than GAAP, if different) of the state or country.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(23)(c))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 944
-SubTopic 505
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477908/944-505-50-1

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- Definition

Amount of net income for the period determined using accounting principles prescribed or permitted by insurance regulators.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(23)(c))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1

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