Derivatives and Hedging Activities 1 (Details) - Interest Expense [Member] - 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	$ (42)	$ (181)	$ 29
Derivatives designated as hedging instruments	45	184	(13)
Total	$ 3	$ 3	$ 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
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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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Total amount of gain (loss) derived from fair value hedges recognized in earnings in the period.

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-Name Accounting Standards Codification
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