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	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Derivative Instruments, Gain (Loss) [Line Items]
Interest expense, net	$ (60)	$ (51)	$ (100)	$ (103)
Designated as Hedging Instrument \| Interest Rate Swap \| Interest Expense
Derivative Instruments, Gain (Loss) [Line Items]
Fair value changes on interest rate swaps	2	20	60	31
Fair value changes on hedged debt	(2)	(20)	(60)	(31)
Designated as Hedging Instrument \| Interest Rate Swap \| Interest Expense \| Fair Value hedge Net Interest Settlements and Accruals
Derivative Instruments, Gain (Loss) [Line Items]
Net interest settlements and accruals on interest rate swaps	$ 5	$ 0	$ 8	$ 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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-Publisher FASB
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-SubTopic 25
-Section 50
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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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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
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The net amount of nonoperating interest income (expense).

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