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Investments (Alternative Investment Portfolio by Strategy and the Remaining Commitment Amount Associated With Each Strategy) (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Carrying Value	$ 91,164	$ 71,244
Private Equity [Member]
Carrying Value	301,759	280,980
Remaining Commitment	131,885	134,676
Maximum Exposure to Loss	433,644	415,656
Private Credit Funds [Member]
Carrying Value	54,500	54,866
Remaining Commitment	89,401	89,481
Maximum Exposure to Loss	143,901	144,347
Real Assets [Member]
Carrying Value	39,520	35,470
Remaining Commitment	33,040	21,945
Maximum Exposure to Loss	72,560	57,415
Alternative Investments [Member]
Carrying Value	395,779	371,316
Remaining Commitment	254,326	246,102
Maximum Exposure to Loss	$ 650,105	$ 617,418

X

- Definition

This item represents contractual obligations to invest additional amounts on our other investment portfolio. These additional investments may or may not be required.

+ References

No definition available.

+ Details

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X

- Definition

Amount of investments classified as other.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(12))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

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X

- Definition

The reporting entity's maximum amount of exposure to loss as a result of its involvement with the Variable Interest Entity (VIE).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph b
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481203/810-10-50-4

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481203/810-10-50-6

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