Summary of Investments (Unrealized Appreciation) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Change in net unrealized investment appreciation
Available-for-sale fixed maturities	$ 7,043	$ 52,556
Available-for-sale equity securities	5,795	1,359
Deferred policy acquisition costs	(1,277)	(11,685)
Income tax effect	(4,046)	(14,781)
Total change in net unrealized investment appreciation, net of tax	$ 7,515	$ 27,449

Equity Securities, Change in Net Unrealized Holding Gain (Loss), Before Tax

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- Definition

This item represents the pretax change in net unrealized holding gain (loss) on available-for-sale securities that has been included in accumulated other comprehensive income, a separate component of shareholders' equity, during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27357-111563

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- Definition

Amount of unrealized investment gain (loss) which decreases (increases) deferred policy acquisition cost.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 30
-Section 35
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=49177698&loc=d3e10138-158409

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-Name Accounting Standards Codification
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-Section 50
-Paragraph 1
-Subparagraph (c)
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No definition available.

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- Definition

Amount after tax, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=66004124&loc=SL7669646-108580

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- Definition

Amount of tax expense (benefit) before reclassification adjustments of unrealized holding gain (loss) on available-for-sale securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
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-Section 45
-Paragraph 10A
-Subparagraph (e,f)
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