Derivatives and Hedging Activities (Details 1) - Interest Expense - Interest Rate Contract - Fair Value Hedging - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Derivative Instruments, Gain (Loss) [Line Items]
Fixed-rate long-term debt	$ 11	$ (66)
Derivatives designated as hedging instruments	(12)	79
Total	$ (1)	$ 13

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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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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