Derivative Instruments And Hedging Activities - Summary of Net Gain (Loss) on Interest Rate Swaps Designated in Fair Value Hedge (Detail) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Derivative Instruments, Gain (Loss) [Line Items]
Interest expense, net	$ (40)	$ (52)
Designated as Hedging Instrument \| Interest Rate Swap \| Interest Expense
Derivative Instruments, Gain (Loss) [Line Items]
Fair value changes on interest rate swaps	58	11
Fair value changes on hedged debt	(58)	(11)
Designated as Hedging Instrument \| Interest Rate Swap \| Interest Expense \| Fair Value hedge Net Interest Settlements and Accruals
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized in income	$ 3	$ 0

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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Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

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The net amount of nonoperating interest income (expense).

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