Derivatives - Fair Value Hedges - IS Location (Details) - Fair value hedges - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Derivatives in Fair Value Hedging Relationships
Gain (Loss) on Derivative Recognized in Income	$ (5)	$ (9)
Gain (Loss) on Hedged Item Recognized in Income	5	9
Interest rate swap contracts \| Interest expense.
Derivatives in Fair Value Hedging Relationships
Gain (Loss) on Derivative Recognized in Income	(5)	(9)
Gain (Loss) on Hedged Item Recognized in Income	$ 5	$ 9

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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
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+ References

No definition available.

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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
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4D
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