Fair Value of Assets and Liabilities (Details 4) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value Measurement with Unobservable Inputs Reconciliation Recurring Basis Sale of Liabilities of Disposal Group Including Discontinued Operations	$ 230
Fair Value, Assets and Liabilities Measured on Recurring Basis, Gain (Loss) Included in Earnings	29	142	228
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Purchases		(117)	0
Rollforward of Level 3 assets held at fair value on a recurring basis
Balance at beginning of period	(553)	(553)	(723)
Total gains (losses) included in: net income	9	109	168
Total gains (losses) included in: OCI	0	0	0
Issues	(18)		(79)
Sales	0	0	0
Settlements	9	8	81
Balance at end of period	(323)	(553)	(553)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	20	33	60
Other investments: Free-standing derivatives	2	9	3
Free Standing Derivative Liabilities, Fair Value Disclosure	9	14	30
Transfer to held for sale		0
Contractholder funds: Derivatives embedded in life and annuity contracts
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value Measurement with Unobservable Inputs Reconciliation Recurring Basis Sale of Liabilities of Disposal Group Including Discontinued Operations	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Purchases		(111)	0
Rollforward of Level 3 assets held at fair value on a recurring basis
Balance at beginning of period	(307)	(553)	(723)
Total gains (losses) included in: net income	(8)	89	168
Total gains (losses) included in: OCI	0	0	0
Issues	(14)		(79)
Sales	0	0	0
Settlements	6	3	81
Balance at end of period	(323)	(307)	(553)
Liabilities held for sale
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value Measurement with Unobservable Inputs Reconciliation Recurring Basis Sale of Liabilities of Disposal Group Including Discontinued Operations	230
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Purchases		(6)
Rollforward of Level 3 assets held at fair value on a recurring basis
Balance at beginning of period	(246)	0
Total gains (losses) included in: net income	17	20	0
Total gains (losses) included in: OCI	0	0
Issues	(4)
Sales	0	0
Settlements	3	5
Balance at end of period	0	(246)	0
Realized capital gains and losses
Rollforward of Level 3 assets held at fair value on a recurring basis
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	11	20	38
Net investment income
Rollforward of Level 3 assets held at fair value on a recurring basis
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	12	14	22
Interest credited to contractholder funds
Rollforward of Level 3 assets held at fair value on a recurring basis
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	(5)	40	132
Contract benefits
Rollforward of Level 3 assets held at fair value on a recurring basis
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	15	74	36
Loss on disposition of operations
Rollforward of Level 3 assets held at fair value on a recurring basis
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	(4)	(6)
CMBS
Rollforward of Level 3 assets held at fair value on a recurring basis
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	0	(1)	(4)
Transfer to held for sale		5
ABS
Rollforward of Level 3 assets held at fair value on a recurring basis
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	0	(2)	24
Transfer to held for sale		85
Lincoln Benefit Life Company \| CMBS
Rollforward of Level 3 assets held at fair value on a recurring basis
Transfer to held for sale	4
Lincoln Benefit Life Company \| ABS
Rollforward of Level 3 assets held at fair value on a recurring basis
Transfer to held for sale	$ 4

Represents the amount of transfer of financial instrument classified as an asset to held for sale.

No definition available.

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Fair Value Measurement with Unobservable Inputs Reconciliation Recurring Basis Sale of Liabilities of Disposal Group Including Discontinued Operations

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No definition available.

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Represents the fair values as of the balance sheet date of all assets resulting from free-standing derivative contracts.

+ References

No definition available.

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Represents the fair values as of the balance sheet date of all liabilities resulting from free-standing derivative contracts.

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No definition available.

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This item represents the amount of the total realized and unrealized gains or losses for the period which are included in the statement of income (or changes in net assets); the fair value of which assets and liabilities was or is measured on a recurring basis using significant unobservable inputs (Level 3).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

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Amount of gain (loss) recognized in the income statement for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of gain (loss) recognized on the income statement for financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of gain (loss) recognized in other comprehensive income (loss) for financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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Amount of issuances of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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-Section 50

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Amount of purchases of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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-Publisher FASB

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Amount of sales of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of settlements of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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