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Investments (Net Investment Income) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Net Investment Income [Line Items]
Net investment income earned	$ 31,182	$ 32,230	$ 61,951	$ 59,147
Fixed Income Securities [Member]
Net Investment Income [Line Items]
Net investment income earned	31,753	30,659	63,397	61,626
Equity Securities [Member]
Net Investment Income [Line Items]
Net investment income earned	2,204	2,384	4,434	4,176
Short-Term Investments [Member]
Net Investment Income [Line Items]
Net investment income earned	142	23	301	48
Other Investments [Member]
Net Investment Income [Line Items]
Net investment income earned	(611)	1,422	(1,677)	(2,118)
Investment Expenses [Member]
Net Investment Income [Line Items]
Net investment income earned	$ (2,306)	$ (2,258)	$ (4,504)	$ (4,585)

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- 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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