Derivative Instruments and Fair Value Measurements - Schedule of Offsetting Assets and Liabilities (Details) - USD ($) $ in Millions	Sep. 30, 2017	Dec. 31, 2016
Offsetting [Abstract]
Asset derivatives, Amounts Presented in the Consolidated Balance Sheet	$ 14	$ 41
Asset derivatives, Financial Instruments, Gross Amounts Not Offset in the Consolidated Balance Sheet	(14)	(24)
Asset derivatives, Cash Collateral Posted, Gross Amounts Not Offset in the Consolidated Balance Sheet	0	0
Asset derivatives, Net Amount	0	17
Liability derivatives, Amounts Presented in the Consolidated Balance Sheet	(71)	(83)
Liability derivatives, Financial Instruments, Gross Amounts Not Offset in the Consolidated Balance Sheet	14	24
Liability derivatives, Cash Collateral Received, Gross Amounts Not Offset in the Consolidated Balance Sheet	16	48
Liability derivatives, net amount	$ (41)	$ (11)

Fair value, after effects of master netting arrangements, deduction of assets not subject to a master netting arrangement and elected not to be offset, of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, offset against an obligation to return collateral.

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Fair value of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, elected not to be offset, deducted from derivative assets.

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Amount of obligation to return cash collateral under master netting arrangements that have not been offset against derivative assets.

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Amount of right to receive cash collateral under master netting arrangements that have not been offset against derivative liabilities.

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+ References

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