Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Aggregate impact of foreign currency derivatives on earnings for the period. Includes impact of foreign currency cash flow hedge ineffectiveness and the ineffectiveness of fair value hedging derivatives and full change in fair value of the foreign currency derivatives not designated as hedging instruments.

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The estimated net amount of unrealized gains or losses on interest rate cash flow hedges as of the balance sheet date expected to be reclassified to earnings within the next twelve months.

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Derivative Instruments and Hedging Activity - Additional Disclosures (Details) $ in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2018 USD ($)	Mar. 31, 2017 USD ($)	Apr. 30, 2018 CAD ($)	Dec. 31, 2017 USD ($)
Interest Rate Swap [Member]
Derivative [Line Items]
Notional amount	$ 8,590			$ 3,609
Net losses included in AOCI expected to be reclassified into interest expense within the next 12 months	5
Foreign Currency Contract [Member] \| Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Notional amount	53			62
Losses related to foreign currency contract	1	$ (1)
Credit Risk Related Contingent Contracts [Member]
Derivative [Line Items]
Fair value of derivative instruments, liabilities	$ 116			$ 17
Subsequent Event [Member] \| Foreign Currency Contract [Member] \| Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Notional amount			$ 741