Reinsurance Level 4 Reinsurance Recoverable (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Reinsurance Recoverables on Paid Losses	$ 133,000,000	$ 138,000,000
Reinsurance Recoverables on Unpaid Losses, Gross	2,868,000,000	2,841,000,000
Premiums Receivable, Allowance for Doubtful Accounts	(271,000,000)	(244,000,000)
Reinsurance Recoverables	22,920,000,000us-gaap_ReinsuranceRecoverables	23,330,000,000us-gaap_ReinsuranceRecoverables
Property, Liability and Casualty Insurance Product Line [Member]
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Gross reinsurance recoverable	3,001,000,000	2,979,000,000
Reinsurance Recoverables	2,730,000,000	2,735,000,000
Life Insurance Product Line [Member]
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Reinsurance Recoverables	20,190,000,000	20,595,000,000
Life Insurance Product Line [Member] \| Continuing Operations [Member]
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Reinsurance Recoverables	1,193,000,000	1,221,000,000
Retirement Plans [Member]
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Reinsurance Recoverables	8,600,000,000	9,500,000,000
Retirement Plans and Individual Life Businesses [Member] \| Life Insurance Product Line [Member]
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Reinsurance Recoverables	18,997,000,000	19,374,000,000
Fair Value of Assets Held in Trust	9,000,000,000
Individual Life [Member]
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Reinsurance Recoverables	10,400,000,000	9,900,000,000
Reinsurance Recoverables [Member]
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Fair Value, Concentration of Risk, Investments	$ 0

The total amount of cash and securities held by third party trustees pursuant to terms of debt instruments or other agreements as of the date of each statement of financial position presented, which can be used by the trustee only to pay the noncurrent portion of specified obligations.

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This item represents disclosure of all significant concentrations of credit risk or market risk arising from the subject financial instrument (as defined), whether from an individual counterparty or groups of counterparties.

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The carrying value as of the balance sheet date of the estimated valuation allowance to reduce gross premiums receivable to net realizable value.

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Amount after valuation allowance recoverable including premium paid under reinsurance contracts. Examples include, but are not limited to, settled and unsettled claims, incurred but not reported losses, loss adjustment expense, premium paid, policy benefits and policy reserves.

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Amount after valuation allowance of reinsurance recoverables on paid losses.

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Amount before valuation allowance of reinsurance recoverables for losses reported to the ceding insurer but not yet paid, and for amounts expected based upon statistical projections and other measures of incurred losses and loss settlement expenses which have not yet been reported to the ceding insurer.

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