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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 | Mar. 31, 2023 | Dec. 31, 2022
--- | --- | ---
Carrying Amount | $ (380,028) | $ (371,316)
Private Equity Funds [Member] |  |
Carrying Amount | (289,598) | (280,980)
Remaining Commitment | 129,839 | 134,676
Maximum Exposure to Loss | 419,437 | 415,656
Private Credit Funds [Member] |  |
Carrying Amount | (53,445) | (54,866)
Remaining Commitment | 89,002 | 89,481
Maximum Exposure to Loss | 142,447 | 144,347
Real Assets [Member] |  |
Carrying Amount | (36,985) | (35,470)
Remaining Commitment | 20,738 | 21,945
Maximum Exposure to Loss | 57,723 | 57,415
Alternative Investments [Member] |  |
Carrying Amount | (380,028) | (371,316)
Remaining Commitment | 239,579 | 246,102
Maximum Exposure to Loss | $ 619,607 | $ 617,418

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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 + Details
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- 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 + Details
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