Derivatives and Hedging Activities (Details 1) - Interest Expense [Member] - Interest Rate Contracts [Member] - Fair Value Hedges [Member] - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Derivative Instruments, Gain (Loss) [Line Items]
Fixed-rate long-term debt	$ (160)	$ 210
Derivatives designated as hedging instruments	158	(191)
Total	$ (2)	$ 19

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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 25
-Section 50
-Paragraph 1
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=109977999&loc=d3e76258-113986

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Amount of the increase (decrease) in fair value of the hedged item in a fair value hedge recognized in the income statement.

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Amount of gain (loss)recognized in the income statement from the hedging ineffectiveness of a fair value hedge.

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