Summary of Investments (Net Realized Investment Gains and Losses) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Gain (Loss) on Investments [Line Items]
Net realized investment gains (losses)	$ 966	$ 894	$ 2,622	$ 5,796
Available-for-sale Securities [Abstract]
Proceeds from sales	0	3,081	8,228	3,091
Gross realized gains	0	900	1,030	900
Gross realized losses	0	0	0	(56)
Fixed Maturities [Member] \| Available-for-sale [Member]
Gain (Loss) on Investments [Line Items]
Net realized investment gains (losses)	407	984	2,363	2,336
Fixed Maturities [Member] \| Trading Securities, Change in Fair Value [Member]
Gain (Loss) on Investments [Line Items]
Net realized investment gains (losses)	(999)	(253)	(1,461)	695
Fixed Maturities [Member] \| Trading Securities, Sales [Member]
Gain (Loss) on Investments [Line Items]
Net realized investment gains (losses)	531	181	1,230	701
Equity Securities [Member] \| Available-for-sale [Member]
Gain (Loss) on Investments [Line Items]
Net realized investment gains (losses)	1,418	0	2,352	1,736
Equity Securities [Member] \| Trading Securities, Change in Fair Value [Member]
Gain (Loss) on Investments [Line Items]
Net realized investment gains (losses)	(430)	(17)	(634)	329
Equity Securities [Member] \| Trading Securities, Sales [Member]
Gain (Loss) on Investments [Line Items]
Net realized investment gains (losses)	39	(1)	85	(1)
Other Long-term Investments [Member]
Gain (Loss) on Investments [Line Items]
Net realized investment gains (losses)	$ 0	$ 0	$ (1,313)	$ 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.

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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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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