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Investments (Net Investment Income) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Net Investment Income [Line Items]
Net investment income earned	$ 41,430	$ 31,182	$ 78,849	$ 61,951
Fixed Income Securities [Member]
Net Investment Income [Line Items]
Net investment income earned	37,668	31,753	74,559	63,397
Equity Securities [Member]
Net Investment Income [Line Items]
Net investment income earned	1,419	2,204	2,887	4,434
Short-Term Investments [Member]
Net Investment Income [Line Items]
Net investment income earned	377	142	627	301
Other Investments [Member]
Net Investment Income [Line Items]
Net investment income earned	5,231	(611)	6,834	(1,677)
Investment Expenses [Member]
Net Investment Income [Line Items]
Net investment income earned	$ (3,265)	$ (2,306)	$ (6,058)	$ (4,504)

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/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(2))
-URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 235
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-16(Column G))
-URI http://asc.fasb.org/extlink&oid=34713774&loc=d3e574960-122915

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- Definition

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+ References

No definition available.

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