Fair Value of Financial Instruments (Details 2) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Investments
Other investments, Carrying Value	$ 7,403,467us-gaap_Investments	$ 6,539,473us-gaap_Investments
Other investments, Fair Value	149,792us-gaap_InvestmentsFairValueDisclosure	144,921us-gaap_InvestmentsFairValueDisclosure
Financial Liabilities
Fixed annuity contract liabilities, Carrying Value	3,774,457	3,515,865
Fixed annuity contract liabilities, Fair value	3,691,123	3,302,333
Policyholder account balances on interest-sensitive life contracts, Carrying Value	77,415	78,598
Policyholder account balances on interest-sensitive life contracts, Fair value	81,461	79,678
Other policyholder funds, Carrying Value	586,689us-gaap_OtherPolicyholderFunds	346,292us-gaap_OtherPolicyholderFunds
Other policyholder funds, Fair Value	586,689	346,292
Short-term debt, Carrying Value	38,000	38,000
Short-term debt, Fair Value	38,000us-gaap_ShorttermDebtFairValue	38,000us-gaap_ShorttermDebtFairValue
Long-term debt, Carrying Value	199,939us-gaap_LongTermDebt	199,874us-gaap_LongTermDebt
Long-term debt, Fair Value	209,495us-gaap_LongTermDebtFairValue	218,565us-gaap_LongTermDebtFairValue
Other liabilities, repurchase agreement obligations, Carrying Value	0	25,864
Other liabilities, repurchase agreement obligations, Fair Value	0	25,864
Level 1 [Member]
Investments
Other investments, Fair Value	0	0
Financial Liabilities
Fixed annuity contract liabilities, Fair value	0	0
Policyholder account balances on interest-sensitive life contracts, Fair value	0	0
Other policyholder funds, Fair Value	0	0
Short-term debt, Fair Value	0	0
Long-term debt, Fair Value	209,495	218,565
Other liabilities, repurchase agreement obligations, Fair Value	0	0
Level 2 [Member]
Investments
Other investments, Fair Value	0	0
Financial Liabilities
Fixed annuity contract liabilities, Fair value	0	0
Policyholder account balances on interest-sensitive life contracts, Fair value	0	0
Other policyholder funds, Fair Value	500,080	250,000
Short-term debt, Fair Value	38,000	38,000
Long-term debt, Fair Value	0	0
Other liabilities, repurchase agreement obligations, Fair Value	0	25,864
Level 3 [Member]
Investments
Other investments, Fair Value	149,792	144,921
Financial Liabilities
Fixed annuity contract liabilities, Fair value	3,691,123	3,302,333
Policyholder account balances on interest-sensitive life contracts, Fair value	81,461	79,678
Other policyholder funds, Fair Value	86,609	96,292
Short-term debt, Fair Value	0	0
Long-term debt, Fair Value	0	0
Other liabilities, repurchase agreement obligations, Fair Value	$ 0	$ 0

Liability for future policy benefits individual and group annuities and supplementary contracts fair value disclosure.

No definition available.

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- Definition

Liability for policy holder account balances life.

+ References

No definition available.

+ Details

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- Definition

Liability for policyholder account balances life fair value.

+ References

No definition available.

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- Definition

Fair Value of the liability as of the balance sheet date to the policyholders for funds held that are returnable under the terms of insurance contracts that were not separately reported.

+ References

No definition available.

+ Details

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- Definition

Sum of the carrying amounts as of the balance sheet date of all investments.

+ References

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-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

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-Paragraph 1

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- Definition

Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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-Section 35

-Paragraph 1

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- Definition

Amount of accrued obligation to policyholders that relates to insured events under individual and group annuities and supplementary insurance contracts.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 40

-Section 25

-Paragraph 11

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-Subparagraph (SX 210.7-03.13(a)(1))

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- Definition

Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

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- Definition

Liability as of the balance sheet date to the policyholders for funds held that are returnable under the terms of insurance contracts that were not separately reported.

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-Publisher FASB

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+ Details

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- Definition

Fair value portion of securities that an entity sells and agrees to repurchase at a specified date for a specified price.

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-Publisher FASB

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-Topic 825

-SubTopic 10

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-Paragraph 10

-URI http://asc.fasb.org/extlink&oid=35750535&loc=d3e13433-108611

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- Definition

Amount, after the effects of master netting arrangements, of funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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- Definition

Carrying amount at the balance sheet date of borrowings from a bank, not elsewhere enumerated in the taxonomy, with a maturity within one year (or within one operating cycle if longer) from the date of borrowing.

+ References

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

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- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents the amount of short-term debt existing as of the balance sheet date.

+ References

No definition available.

+ Details

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