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Investments (Net Investment Income) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Net Investment Income [Line Items]
Net investment income earned	$ 50,618	$ 43,231
Fixed Income Securities [Member]
Net Investment Income [Line Items]
Net investment income earned	49,033	42,041
Equity Securities [Member]
Net Investment Income [Line Items]
Net investment income earned	1,640	1,977
Short-Term Investments [Member]
Net Investment Income [Line Items]
Net investment income earned	2,044	523
Other Investments [Member]
Net Investment Income [Line Items]
Net investment income earned	660	1,563
Investment Expenses [Member]
Net Investment Income [Line Items]
Net investment income earned	$ (2,759)	$ (2,873)

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=114873790&loc=SL114874131-224263

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+ References

No definition available.

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