Investments (Net Unrealized Gain (Loss) on Investments) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Investments, Debt and Equity Securities [Abstract]
Gross unrealized gains	$ 157,304us-gaap_UnrealizedGainOnSecurities	$ 159,080us-gaap_UnrealizedGainOnSecurities
Gross unrealized losses	(12,926)us-gaap_UnrealizedLossOnSecurities	(37,263)us-gaap_UnrealizedLossOnSecurities
Deferred policy acquisition costs and sales inducements	(62,856)	(51,929)
Deferred federal income tax expense	(28,556)	(24,484)
Adjustments for deferred expense, deferred policy acquisition and sales inducement cost	52,966	45,404
Net unrealized gains related to securities transferred to held to maturity	0	0
Net unrealized gains on investment securities	$ 52,966us-gaap_UnrealizedGainLossOnInvestments	$ 45,404us-gaap_UnrealizedGainLossOnInvestments

Adjustment for Deferred Tax Expense, Deferred Policy Acquisition and Sales Inducement Cost

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- Definition

Deferred Federal Income Tax Expense (Benefit), Net Unrealized Gain on Investments

+ References

No definition available.

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- Definition

Deferred Policy Acquisition Costs and Sales Inducements1

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No definition available.

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- Definition

Net Unrealized Gains Related to Securities Transferred to Held-to-Maturity

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No definition available.

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- Definition

The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of investments, not including unrealized gains or losses on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity, held at each balance sheet date and included in earnings for the period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

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- Definition

The increase (decrease), resulting in a gain, in the difference between the fair value and the carrying value, or in the comparative fair values, of securities held at each balance sheet date, that was included in earnings for the period.

+ References

No definition available.

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- Definition

The increase (decrease), resulting in a loss, in the difference between the fair value and the carrying value, or in the comparative fair values, of securities held at each balance sheet date, that was included in earnings for the period.

+ References

No definition available.

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