INVESTMENTS - Mortgage Loans (Narrative) (Details)	3 Months Ended	12 Months Ended
Mar. 31, 2025 USD ($) loan	Dec. 31, 2024 USD ($)	Mar. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)
Debt and Equity Securities, FV-NI [Line Items]
Weighted average debt service coverage ratios	1.7	1.7
Weighted average loan-to-value ratios (as a percent)	78.00%	78.00%
Number of commercial mortgage loans, past due \| loan	1
Commercial mortgage loans, past due amount			$ 0
Allowance for expected credit losses	$ 25,862,000	$ 23,378,000	$ 8,113,000	$ 6,220,000
Sector Concentration \| Mortgage Loans \| Mortgage Loans
Debt and Equity Securities, FV-NI [Line Items]
Representation (as a percent)	47.00%	43.00%

This item represents the amortized cost of commercial mortgage loans held for investments that are past due.

No definition available.

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- Definition

Number Of Mortgage Loans, Held For Investment, Past Due

+ References

No definition available.

+ Details

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- Definition

Weighted Average Debt Service Coverage Ratios

+ References

No definition available.

+ Details

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- Definition

Weighted average loan-to-value ratios

+ References

No definition available.

+ Details

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
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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
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