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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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- Definition

The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

+ References

No definition available.

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
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-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5618551-113959

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- Definition

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.

+ References

No definition available.

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- Definition

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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4D
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Derivatives - Fair Value Hedges (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2018	Sep. 30, 2017
Fixed rate medium term note due 2021
Derivatives in Fair Value Hedging Relationships
Principal amount	$ 400	$ 400
Interest rate swap contracts \| Fixed rate medium term note due 2021
Derivatives in Fair Value Hedging Relationships
Derivative notional amount	$ 200	200
Variable rate	three-month LIBOR
Fair value hedges
Derivatives in Fair Value Hedging Relationships
Gain (Loss) on Derivative Recognized in income		(12)	$ (4)
Gain (Loss) on Hedged Item Recognized in Income		12	4
Fair value hedges \| Interest rate swap contracts \| Interest expense.
Derivatives in Fair Value Hedging Relationships
Gain (Loss) on Derivative Recognized in income		(12)	(4)
Gain (Loss) on Hedged Item Recognized in Income		$ 12	$ 4