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Investments (Alternative Investment Portfolio by Strategy and the Remaining Commitment Amount and Maximum Exposure to Loss Associated With Each Strategy) (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Carrying Amount	$ 389,173	$ 371,316
Private Equity Funds [Member]
Carrying Amount	298,219	280,980
Remaining Commitment	124,213	134,676
Maximum Exposure to Loss	422,432	415,656
Private Credit Funds [Member]
Carrying Amount	52,379	54,866
Remaining Commitment	138,691	89,481
Maximum Exposure to Loss	191,070	144,347
Real Assets [Member]
Carrying Amount	38,575	35,470
Remaining Commitment	19,553	21,945
Maximum Exposure to Loss	58,128	57,415
Alternative Investments [Member]
Carrying Amount	389,173	371,316
Remaining Commitment	282,457	246,102
Maximum Exposure to Loss	$ 671,630	$ 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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- Definition

Fair value of investment other than investment in equity security, investment in debt security and equity method investment. Includes, but is not limited to, investment in certain entities that calculate net asset value per share. Example includes, but is not limited to, investment in hedge fund, venture capital fund, private equity fund, and real estate partnership or fund.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 6A
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126976982&loc=SL6742756-110258

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 35
-Paragraph 54B
-URI https://asc.fasb.org/extlink&oid=126972413&loc=SL7495116-110257

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=123419778&loc=d3e5747-111685

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph b
-URI https://asc.fasb.org/extlink&oid=123419778&loc=d3e5728-111685

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