Derivatives and Hedging Activities (Details 1) - Interest Expense - Interest Rate Contract - Fair Value Hedging - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Derivative Instruments, Gain (Loss) [Line Items]
Fixed-rate long-term debt	$ 59	$ 96	$ 257	$ (497)
Derivatives designated as hedging instruments	(58)	(97)	(257)	504
Total	$ 1	$ (1)	$ 0	$ 7

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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