Schedule I: Summary of Investments - Other Than Investments in Related Parties (Parenthetical) (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Loaned securities	$ 139,121	$ 203,693
Reinvested cash collateral held under securities lending agreements	125,723	$ 149,364
Loaned securities
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Loaned securities	130,000
Trading securities
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Reinvested cash collateral held under securities lending agreements	126,000
Equity securities \| Loaned securities
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Loaned securities	9,000
Short-term investments \| Loaned securities
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Loaned securities	$ 464

Reinvested Cash Collateral Held Under Securities Lending Agreements

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-X (SX)
-Number 210
-Section 12
-Subsection 15
-Publisher SEC

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 320
-Name Accounting Standards Codification
-Section S99
-Paragraph 7
-Subparagraph (SX 210.12-15)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477271/946-320-S99-7

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- Definition

Amount of asset associated with securities loaned to entities in exchange for collateral.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 55
-Paragraph 8
-SubTopic 20
-Topic 210
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483444/210-20-55-8

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483466/210-20-50-3

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