The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

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Amount of gain (loss) from the increase (decrease) in fair value of derivative and nonderivative instruments designated as fair value hedging instruments recognized in the income statement.

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The amount of net gains or losses on foreign currency cash flow hedges reclassified during the period to earnings from accumulated other comprehensive income upon the hedged transaction affecting earnings.

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Amount of cumulative increase (decrease) in fair value of hedged asset in fair value hedge, attributable to hedged risk.

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Amount of net unrealized gain (loss) related to the change in fair value of foreign currency exchange rate derivatives designated as cash flow hedging instruments. Recorded in accumulated other comprehensive income to the extent that the cash flow hedge is determined to be effective.

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Derivative Instruments - Narrative (Details) - Derivatives designated as hedges - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Cash flow hedges \| Foreign currency swaps
Derivative [Line Items]
Foreign currency swap gains (losses)	$ 124,000,000	$ 7,000,000	$ 171,000,000	$ 52,000,000
Foreign currency swap gain (loss) reclassified to income			0	$ 0
Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months			0
Fair Value Hedging [Member] \| Foreign currency forwards
Derivative [Line Items]
Derivative, Amount of Hedged Item	347,000,000		347,000,000		$ 88,000,000
Hedged Asset, Fair Value Hedge, Cumulative Increase (Decrease)	(11,000,000)		(11,000,000)		$ 1,000,000
Change in Unrealized Gain (Loss) on Fair Value Hedging Instruments	13,000,000		13,000,000
Change in Unrealized Gain (Loss) on Hedged Item in Fair Value Hedge	$ (11,000,000)		$ (12,000,000)