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Amount of the collateral pledged in support of federal home loan bank advances outstanding.

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Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

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The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

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Borrowings and Financing Activities - Additional Information (Details)		3 Months Ended	9 Months Ended
	Nov. 04, 2025 USD ($)	Jun. 30, 2025 USD ($)	Sep. 30, 2025 USD ($)	Dec. 31, 2024 USD ($)
Total fixed-maturities available for sale \| Fixed maturities AFS and trading securities
Debt Instrument [Line Items]
FHLB, collateral pledged			$ 65,000,000	$ 49,000,000
FHLB Advances \| Minimum
Debt Instrument [Line Items]
FHLB, ratio of market value of collateral to advances			1.03
FHLB Advances \| Maximum
Debt Instrument [Line Items]
FHLB, ratio of market value of collateral to advances			1.14
Revolving Credit Facility
Debt Instrument [Line Items]
Fair value of amount outstanding			$ 0
Borrowed debt		$ 50,000,000
Repayment of debt		$ 50,000,000
Revolving Credit Facility \| Unsecured Revolving Credit Facility, Expiration Date 2026
Debt Instrument [Line Items]
Current borrowing capacity			$ 275,000,000
Revolving Credit Facility \| Unsecured Revolving Credit Facility, Maturity date November 2030 \| Subsequent Event
Debt Instrument [Line Items]
Line of credit facility, increase, committed borrowing capacity	$ 500,000,000
Maturity date	Nov. 04, 2030
Line of credit facility, higher borrowing capacity option	$ 250,000,000