Summary of Investments (Net Realized Investment Gains and Losses) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Gain (Loss) on Investments [Line Items]
Total net realized investment gains	$ 2,590	$ 966	$ 6,241	$ 2,622
Available-for-sale Securities [Abstract]
Proceeds from sales	2,007	0	5,049	8,228
Gross realized gains	11	0	986	1,030
Fixed maturities: \| Available-for-sale
Gain (Loss) on Investments [Line Items]
Total net realized investment gains	945	407	2,307	2,363
Fixed maturities: \| Change in fair value
Gain (Loss) on Investments [Line Items]
Total net realized investment gains	148	(999)	519	(1,461)
Fixed maturities: \| Sales
Gain (Loss) on Investments [Line Items]
Total net realized investment gains	107	531	568	1,230
Equity securities: \| Available-for-sale
Gain (Loss) on Investments [Line Items]
Total net realized investment gains	1,375	1,418	2,359	2,352
Equity securities: \| Change in fair value
Gain (Loss) on Investments [Line Items]
Total net realized investment gains	(5)	(430)	325	(634)
Equity securities: \| Sales
Gain (Loss) on Investments [Line Items]
Total net realized investment gains	20	39	(6)	85
Other long-term investments
Gain (Loss) on Investments [Line Items]
Total net realized investment gains	0	0	0	(1,313)
Cash equivalents
Gain (Loss) on Investments [Line Items]
Total net realized investment gains	$ 0	$ 0	$ 169	$ 0

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This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

+ 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 (a)
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The cash inflow associated with the sale of debt and equity securities classified as available-for-sale securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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The net realized gains or losses on investments during the period, not including gains or losses on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 225
-Section S99
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-Subparagraph (SX 210.7-04.3(a))
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