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Investments (Net Investment Income) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Net Investment Income [Line Items]
Net investment income earned	$ 91,506	$ 72,602
Fixed Income Securities [Member]
Net Investment Income [Line Items]
Net investment income earned	80,087	53,925
Commercial Mortgage Loans [Member]
Net Investment Income [Line Items]
Net investment income earned	1,965	970
Equity Securities [Member]
Net Investment Income [Line Items]
Net investment income earned	1,205	2,418
Short-Term Investments [Member]
Net Investment Income [Line Items]
Net investment income earned	4,650	101
Alternative Investments [Member]
Net Investment Income [Line Items]
Net investment income earned	7,768	19,128
Other Investments [Member]
Net Investment Income [Line Items]
Net investment income earned	43	177
Investment expenses [Member]
Net Investment Income [Line Items]
Net investment income earned	$ (4,212)	$ (4,117)

X

- Definition

Amount, after investment expense, of income earned from investments in securities and real estate. Includes, but is not limited to, real estate investment, policy loans, dividends, and interest. Excludes realized gain (loss) on investments.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(2))
-URI https://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263

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- Definition

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+ References

No definition available.

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