Financial Instruments, Hedging Activities and Fair Value Measurements (Additional Information) (Detail) € in Billions	12 Months Ended
	Dec. 31, 2020 EUR (€)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Aug. 30, 2019 USD ($)	Dec. 31, 2018 USD ($)	Feb. 28, 2018 USD ($)	Dec. 31, 2017 USD ($)
Derivative Instruments and Hedging Activities Disclosure [Line Items]
Finance lease liability		$ 12,000,000
Notional Amount of Derivative Instruments Designated as Net Investment Hedges						$ 560,000,000
Fair Value of Debt Instrument Designated as a Hedge of Net Investment in Foreign Operations		2,400,000,000	$ 2,200,000,000
Accumulated pretax unrealized translation gains		5,815,000,000	5,403,000,000		$ 4,732,000,000		$ 5,672,000,000
Cash Flow Hedging
Derivative Instruments and Hedging Activities Disclosure [Line Items]
Foreign Currency Contracts, Liability, Fair Value Disclosure		1,000,000	1,000,000
Notional Amount of Derivative Instruments Designated as Net Investment Hedges			43,000,000
Net Investment Hedging
Derivative Instruments and Hedging Activities Disclosure [Line Items]
Notional Amount of Derivative Instruments Designated as Net Investment Hedges						575,000,000
Notional Amount of Nonderivative Instruments | €	€ 2.0
Foreign Currency Contracts
Derivative Instruments and Hedging Activities Disclosure [Line Items]
Foreign Currency Contracts, Liability, Fair Value Disclosure		2,000,000
Foreign Currency Contracts, Liability, Fair Value Disclosure		6,000,000	6,000,000
Notional Amount of Derivative Instruments Designated as Net Investment Hedges		1,400,000,000	2,800,000,000
Interest Rate Swap
Derivative Instruments and Hedging Activities Disclosure [Line Items]
Notional Amount of Derivative Instruments Designated as Net Investment Hedges						$ 525,000,000
Interest Rate Derivatives, at Fair Value, Net		67,000,000	35,000,000
Cross Currency Swaps
Derivative Instruments and Hedging Activities Disclosure [Line Items]
Derivative Instruments in Hedges, Net Investment in Foreign Operations, Assets, Fair Value, Net		8,000,000	48,000,000
Currency Swap
Derivative Instruments and Hedging Activities Disclosure [Line Items]
Notional Amount of Derivative Instruments Designated as Net Investment Hedges				$ 300,000,000
Designated as Hedging Instrument | Foreign Currency Contracts | Cash Flow Hedging | Settlement Date 15 March 2018
Derivative Instruments and Hedging Activities Disclosure [Line Items]
Notional Amount of Derivative Instruments Designated as Net Investment Hedges			560,000,000
Accumulated Gain (Loss), Cash Flow Hedge, Including Noncontrolling Interest
Derivative Instruments and Hedging Activities Disclosure [Line Items]
Accumulated pretax unrealized translation gains		$ 22,000,000	$ 235,000,000