Derivatives - Fair Value Hedges (Details) - Fair value hedges $ in Millions	9 Months Ended
Sep. 30, 2018 USD ($)
Derivatives in Fair Value Hedging Relationships
Gain (Loss) on Derivative Recognized in Income	$ (12)
Gain (Loss) on Hedged Item Recognized in Income	12
Interest rate swap contracts \| Interest expense.
Derivatives in Fair Value Hedging Relationships
Gain (Loss) on Derivative Recognized in Income	(12)
Gain (Loss) on Hedged Item Recognized in Income	$ 12

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

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The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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