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Investments (Net Investment Income) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Net Investment Income [Line Items]
Net investment income earned	$ 33,375	$ 32,061	$ 95,326	$ 91,208
Fixed Income Securities [Member]
Net Investment Income [Line Items]
Net investment income earned	32,453	30,601	95,850	92,227
Equity Securities [Member]
Net Investment Income [Line Items]
Net investment income earned	1,506	2,370	5,940	6,546
Short-Term Investments [Member]
Net Investment Income [Line Items]
Net investment income earned	192	24	493	72
Other Investments [Member]
Net Investment Income [Line Items]
Net investment income earned	1,628	1,337	(49)	(781)
Investment Expenses [Member]
Net Investment Income [Line Items]
Net investment income earned	$ (2,404)	$ (2,271)	$ (6,908)	$ (6,856)

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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