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Investments (Net Investment Income) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Net Investment Income [Line Items]
Net investment income earned	$ 34,444	$ 58,505	$ 90,411	$ 109,123
Fixed Income Securities [Member]
Net Investment Income [Line Items]
Net investment income earned	51,079	50,907	101,332	99,940
Commercial Mortgage Loans [Member]
Net Investment Income [Line Items]
Net investment income earned	156	0	218	0
Equity Securities [Member]
Net Investment Income [Line Items]
Net investment income earned	2,023	1,740	3,575	3,380
Short-Term Investments [Member]
Net Investment Income [Line Items]
Net investment income earned	420	1,759	1,586	3,803
Other Investments [Member]
Net Investment Income [Line Items]
Net investment income earned	(15,846)	7,494	(9,504)	8,154
Investment Expenses [Member]
Net Investment Income [Line Items]
Net investment income earned	$ (3,388)	$ (3,395)	$ (6,796)	$ (6,154)

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 http://asc.fasb.org/extlink&oid=116637232&loc=SL114874131-224263

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- Definition

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+ References

No definition available.

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