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Derivative Instruments And Hedging Activities - Additional Information (Detail)	1 Months Ended
	Jan. 31, 2020 USD ($)	Jun. 30, 2021 USD ($)	Jun. 30, 2021 EUR (€)	Dec. 31, 2020 USD ($)	Apr. 30, 2020 USD ($)
Derivative [Line Items]
Cumulative loss		$ 425,000,000		$ 432,000,000
Designated as Hedging Instrument
Derivative [Line Items]
Cumulative loss		164,000,000		269,000,000
Net Investment Hedging \| Designated as Hedging Instrument
Derivative [Line Items]
Cumulative loss		116,000,000		220,000,000
Net Investment Hedging \| Designated as Hedging Instrument \| Cross-currency swap
Derivative [Line Items]
Notional Amount \| €			€ 2,019,000,000
Cumulative loss		70,000,000		124,000,000
Cash Flow Hedging \| Forward Contracts
Derivative [Line Items]
Cumulative loss					$ 68,000,000
Cash Flow Hedging \| Designated as Hedging Instrument
Derivative [Line Items]
Cumulative loss		48,000,000		49,000,000
Cash Flow Hedging \| Designated as Hedging Instrument \| Cross-currency swap
Derivative [Line Items]
Cumulative loss		$ (2,000,000)		$ (2,000,000)
Cash Flow Hedging \| Designated as Hedging Instrument \| Forward Contracts
Derivative [Line Items]
Notional Amount	$ 300,000,000
Forward interest rate	2.0103%
Debt instrument, term	30 years
1.75% 2015 Senior Notes, due 2027
Derivative [Line Items]
Notes payable, interest rate		1.75%	1.75%	1.75%
1.75% 2015 Senior Notes, due 2027 \| Net Investment Hedging \| Designated as Hedging Instrument \| Cross-currency swap
Derivative [Line Items]
Notional Amount \| €			€ 500,000,000
2019 Senior Notes Due 2030 \| Net Investment Hedging \| Designated as Hedging Instrument \| Cross-currency swap
Derivative [Line Items]
Notional Amount \| €			€ 750,000,000
3.25% 2020 Senior Notes, due 2050
Derivative [Line Items]
Notes payable, interest rate		3.25%	3.25%	3.25%