Financial Instruments and Fair Value Measurements - Summary of Undesignated Foreign Currency Forwards Activity (Detail) - Forwards [Member] - Undesignated Derivatives [Member]	12 Months Ended
	Dec. 31, 2020 USD ($) Derivative	Dec. 31, 2019 USD ($) Derivative	Dec. 31, 2018 USD ($) Derivative
Derivative [Line Items]
Notional amounts at January 1	$ 1,107,000,000	$ 669,000,000	$ 574,000,000
New contracts	2,005,000,000	2,571,000,000	860,000,000
Matured, expired or settled contracts	(1,950,000,000)	(2,133,000,000)	(765,000,000)
Notional amounts at December 31	$ 1,162,000,000	1,107,000,000	669,000,000
Weighted average forward rate at December 31	0
Active contracts at December 31 | Derivative	0
CAD
Derivative [Line Items]
Notional amounts at January 1	$ 120,000,000	55,000,000	56,000,000
New contracts	88,000,000	201,000,000	28,000,000
Matured, expired or settled contracts	(45,000,000)	(136,000,000)	(29,000,000)
Notional amounts at December 31	$ 163,000,000	$ 120,000,000	$ 55,000,000
Weighted average forward rate at December 31	1.32	1.32	1.28
Active contracts at December 31 | Derivative	58	40	24
EUR
Derivative [Line Items]
Notional amounts at January 1	$ 581,000,000	$ 314,000,000	$ 233,000,000
New contracts	1,314,000,000	619,000,000	252,000,000
Matured, expired or settled contracts	(1,421,000,000)	(352,000,000)	(171,000,000)
Notional amounts at December 31	$ 474,000,000	$ 581,000,000	$ 314,000,000
Weighted average forward rate at December 31	1.23	1.13	1.21
Active contracts at December 31 | Derivative	64	53	35
GBP
Derivative [Line Items]
Notional amounts at January 1	$ 178,000,000	$ 118,000,000	$ 132,000,000
New contracts	364,000,000	1,111,000,000	55,000,000
Matured, expired or settled contracts	(335,000,000)	(1,051,000,000)	(69,000,000)
Notional amounts at December 31	$ 207,000,000	$ 178,000,000	$ 118,000,000
Weighted average forward rate at December 31	1.32	1.32	1.32
Active contracts at December 31 | Derivative	53	50	24
JPY
Derivative [Line Items]
Notional amounts at January 1	$ 182,000,000	$ 177,000,000	$ 153,000,000
New contracts	154,000,000	85,000,000	102,000,000
Matured, expired or settled contracts	(84,000,000)	(80,000,000)	(78,000,000)
Notional amounts at December 31	$ 252,000,000	$ 182,000,000	$ 177,000,000
Weighted average forward rate at December 31	102.66	103.39	105.17
Active contracts at December 31 | Derivative	59	44	34
SEK
Derivative [Line Items]
Notional amounts at January 1	$ 31,000,000	$ 0
New contracts	37,000,000	31,000,000
Matured, expired or settled contracts	(30,000,000)	0
Notional amounts at December 31	$ 38,000,000	$ 31,000,000	$ 0
Weighted average forward rate at December 31	8.64	9.42
Active contracts at December 31 | Derivative	42	20
Other
Derivative [Line Items]
Notional amounts at January 1	$ 15,000,000	$ 5,000,000	0
New contracts	48,000,000	524,000,000	423,000,000
Matured, expired or settled contracts	(35,000,000)	(514,000,000)	(418,000,000)
Notional amounts at December 31	$ 28,000,000	$ 15,000,000	$ 5,000,000
Weighted average forward rate at December 31	0
Active contracts at December 31 | Derivative	0