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

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount before tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Financial Instruments, Hedging Activities and Fair Value Measurements (Fair Value, Cash Flow and Net Investment Hedges) (Detail) $ in Millions, € in Billions	12 Months Ended
	Dec. 31, 2020 EUR (€)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Fair Value Hedging
Derivatives, Fair Value [Line Items]
Gain (Loss) Recognized Amount		$ 12	$ 3	$ 3
Fair Value Hedging \| Foreign Currency Contracts \| Interest expense
Derivatives, Fair Value [Line Items]
Gain (Loss) Recognized Amount		12	3	3
Cash Flow Hedging
Derivatives, Fair Value [Line Items]
Gain (Loss) Deferred in OCI		0	2	(9)
Gain (Loss) Recognized Amount		0	(3)	(8)
Cash Flow Hedging \| Foreign Currency Contracts \| Other Expense
Derivatives, Fair Value [Line Items]
Gain (Loss) Deferred in OCI		0	2	(9)
Gain (Loss) Recognized Amount		0	(3)	(8)
Net Investment Hedging
Derivatives, Fair Value [Line Items]
Notional Amount of Nonderivative Instruments \| €	€ 2.0
Gain (Loss) Deferred in OCI		(257)	74	145
Gain (Loss) Recognized Amount		16	18	13
Net Investment Hedging \| Currency Swap
Derivatives, Fair Value [Line Items]
Gain (Loss) Deferred in OCI		(57)	13	21
Gain (Loss) Recognized Amount		16	18	13
Net Investment Hedging \| Other Foreign Currency Denominated Debt
Derivatives, Fair Value [Line Items]
Gain (Loss) Deferred in OCI		(200)	61	124
Economic Hedging \| Foreign Currency Contracts \| Other Expense
Derivatives, Fair Value [Line Items]
Gain (Loss) Recognized Amount		$ 30	$ 55	$ 55