Derivatives and Hedging Activities (Details 1) - Interest Rate Contracts [Member] - Fair Value Hedging [Member] - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Derivative Instruments, Gain (Loss) [Line Items]
Fixed-rate long-term debt	$ (405)	$ (458)	$ 59
Derivatives designated as hedging instruments	409	462	(43)
Total	$ 4	$ 4	$ 16

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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 25
-Section 50
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- Definition

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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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.

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Total amount of gain (loss) derived from fair value hedges recognized in earnings in the period.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
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