Financial Instruments and Fair Value Measurements - Summary of Activity in Interest Rate Swaps (Detail) - Interest Rate Swap [Member] - Cash Flow Hedges [Member] - Designated As Hedging Instrument [Member] - USD ($)	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
Derivative [Line Items]
Notional amounts at January 1	$ 415,000,000	$ 0
New contracts	0	1,165,000,000
Matured, expired or settled contracts	(250,000,000)	(750,000,000)
Notional amounts at June 30	165,000,000	415,000,000
EUR
Derivative [Line Items]
Notional amounts at January 1	165,000,000	0
New contracts	0	165,000,000
Matured, expired or settled contracts	0	0
Notional amounts at June 30	165,000,000	165,000,000
USD
Derivative [Line Items]
Notional amounts at January 1	250,000,000	0
New contracts	0	1,000,000,000
Matured, expired or settled contracts	(250,000,000)	(750,000,000)
Notional amounts at June 30	$ 0	$ 250,000,000