Income Taxes Level 4 Net Operating Loss Carryover (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Dec. 31, 2014
Operating Loss Carryforwards [Line Items]
Deferred Tax Assets, Operating Loss Carryforwards, Subject to Expiration	5,485	$ 5,547
Deferred Tax Assets, Operating Loss Carryforwards	1,915	1,936
Tax Credit Carryforward, Valuation Allowance	8
Earliest Tax Year [Member]
Operating Loss Carryforwards [Line Items]
Operating Loss Carryforwards, Expiration Date	Dec. 31, 2016
Expiring within Tax Years 2016 to 2017 [Member]
Operating Loss Carryforwards [Line Items]
Deferred Tax Assets, Operating Loss Carryforwards, Subject to Expiration	3
Latest Tax Year [Member]
Operating Loss Carryforwards [Line Items]
Operating Loss Carryforwards, Expiration Date	Dec. 31, 2033
Expiring within Tax Years 2023 to 2033 [Member]
Operating Loss Carryforwards [Line Items]
Deferred Tax Assets, Operating Loss Carryforwards, Subject to Expiration	5,482
Foreign [Member]
Operating Loss Carryforwards [Line Items]
Deferred Tax Assets, Operating Loss Carryforwards, Subject to Expiration	34	39
Before Tax [Member] \| UNITED STATES
Operating Loss Carryforwards [Line Items]
Deferred Tax Assets, Operating Loss Carryforwards, Subject to Expiration	5,451	$ 5,508

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards.

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-Name Accounting Standards Codification

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Expiration date of each operating loss carryforward included in operating loss carryforward, in CCYY-MM-DD format.

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Amount of valuation allowance pertaining to the deferred tax asset representing potential future taxable deductions from tax credit carryforwards for which it is more likely than not that a tax benefit will not be realized.

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