Investments - Schedule of 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
Realized Investment Gains Losses [Abstract]
Gross gains from sales	$ 1,209	$ 550	$ 4,610	$ 1,731
Gross losses from sales	(26)	(115)	(285)	(160)
Other-than-temporary impairment losses	(1,564)	(515)	(2,433)	(885)
Gains (losses) from bifurcated options	122	(201)	(269)	127
Realized investment gains (losses), including other-than- temporary impairment losses	(259)	(281)	1,623	813
Tax expense (benefit) associated with unrealized holding gains (losses) recognized in other comprehensive income on investment securities	(6,249)	(7,468)	(13,810)	5,550
Tax expense (benefit) associated with net unrealized investment losses other-than-temporarily impaired recognized in other comprehensive income	208	477	208	477
Tax expense (benefit) associated with realized investment gains (losses) reclassified from accumulated other comprehensive income into earnings	(133)	(28)	662	240
Proceeds from sales or other redemptions	$ 96,285	$ 92,130	$ 310,519	$ 301,519

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 total amount of proceeds received for the sale of securities, categorized neither as held-to-maturity nor trading securities, during the reporting period.

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

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Net Increase or Decrease in the fair value of the embedded derivative or group of embedded derivatives included in earnings in the period.

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

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-Name Accounting Standards Codification

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Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

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

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Amount of tax (expense) benefit of other than temporary impairment (OTTI) on investment in available-for-sale debt security, recognized in other comprehensive loss, attributable to the parent entity.

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The amount of other than temporary impairment losses on investments in debt and equity securities categorized as Available-for-sale which have been recognized in earnings during the period. Such impairment losses consist of other than temporary impairments (OTTI) on equity securities, credit losses on investments in debt securities, and when the entity intends to sell an impaired debt security or it is more likely than not that the entity will be required to sell the impaired debt security before recovery of its amortized cost basis.

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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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