Financial Instruments and Fair Value Measurements - Foreign Currency Contracts Activity (Detail)	6 Months Ended
	Jun. 30, 2016 USD ($) Derivative $ / € £ / $ ¥ / $ CAD / $ € / $	Jun. 30, 2016 EUR (€) Derivative $ / € £ / $ ¥ / $ CAD / $ € / $		Jun. 30, 2016 JPY (¥) Derivative $ / € £ / $ ¥ / $ CAD / $ € / $		Jun. 30, 2016 GBP (£) Derivative $ / € £ / $ ¥ / $ CAD / $ € / $		Jun. 30, 2016 CAD Derivative $ / € £ / $ ¥ / $ CAD / $ € / $	Jun. 30, 2015 USD ($)	Jun. 30, 2015 EUR (€)	Jun. 30, 2015 JPY (¥)	Jun. 30, 2015 GBP (£)	Jun. 30, 2015 CAD
Net Investment Forward Contracts [Member] | GBP [Member]
Derivative [Line Items]
Notional amounts at January 1	$ 386,000,000					£ 238,000,000			$ 400,000,000			£ 238,000,000
New contracts	85,000,000					60,000,000			186,000,000			118,000,000
Matured or expired contracts	(100,000,000)					(60,000,000)			(200,000,000)			(118,000,000)
Notional amounts at June 30	$ 371,000,000					£ 238,000,000			386,000,000			238,000,000
Weighted average forward rate at June 30 | £ / $	1.56	1.56		1.56		1.56		1.56
Active contracts at June 30	3	3		3		3		3
Net Investment Forward Contracts [Member] | JPY
Derivative [Line Items]
Notional amounts at January 1	$ 0			¥ 0					250,000,000		¥ 24,136,000,000
New contracts	99,000,000			11,189,000,000					353,000,000		43,373,000,000
Matured or expired contracts	(99,000,000)			(11,189,000,000)					(603,000,000)		(67,509,000,000)
Notional amounts at June 30	$ 0			¥ 0					0		0
Weighted average forward rate at June 30 | ¥ / $	0	0		0		0		0
Active contracts at June 30	0	0		0		0		0
Net Investment Forward Contracts [Member] | CAD
Derivative [Line Items]
Notional amounts at January 1	$ 0							CAD 0
New contracts	100,000,000							133,000,000
Matured or expired contracts	0							0
Notional amounts at June 30	$ 100,000,000							CAD 133,000,000
Weighted average forward rate at June 30 | CAD / $	1.33	1.33		1.33		1.33		1.33
Active contracts at June 30	2	2		2		2		2
Net Investment Forward Contracts [Member] | EUR
Derivative [Line Items]
Notional amounts at January 1									400,000,000	€ 300,000,000
New contracts									0	0
Matured or expired contracts									(400,000,000)	(300,000,000)
Notional amounts at June 30									0	0
Forward and Option Contracts [Member]
Derivative [Line Items]
Notional amounts at June 30		€ 8,000,000				£ 6,000,000
Weighted average forward rate at June 30 | $ / €	1.45	1.45		1.45		1.45		1.45
Forward and Option Contracts [Member] | GBP [Member]
Derivative [Line Items]
Notional amounts at January 1	$ 148,000,000					£ 97,000,000	[1],[2]		0			0
New contracts	0					0	[1],[2]		188,000,000			126,000,000
Matured or expired contracts	(36,000,000)					(24,000,000)	[1],[2]		(79,000,000)			(53,000,000)
Notional amounts at June 30	$ 112,000,000					£ 73,000,000	[1],[2]		109,000,000			£ 73,000,000
Weighted average forward rate at June 30 | £ / $	1.53	1.53		1.53		1.53		1.53
Active contracts at June 30	12	12		12		12		12
Forward and Option Contracts [Member] | JPY
Derivative [Line Items]
Notional amounts at January 1	$ 109,000,000			¥ 12,840,000,000	[1]				0		0
New contracts	108,000,000			11,460,000,000	[1]				109,000,000		12,740,000,000
Matured or expired contracts	(27,000,000)			(3,120,000,000)	[1]				(24,000,000)		(2,800,000,000)
Notional amounts at June 30	$ 190,000,000			¥ 21,180,000,000	[1]				85,000,000		¥ 9,940,000,000
Weighted average forward rate at June 30 | ¥ / $	112.00	112.00		112.00		112.00		112.00
Active contracts at June 30	33	33		33		33		33
Forward and Option Contracts [Member] | CAD
Derivative [Line Items]
Notional amounts at January 1									0				CAD 0
New contracts									40,000,000				49,000,000
Matured or expired contracts									(6,000,000)				(7,000,000)
Notional amounts at June 30									34,000,000				CAD 42,000,000
Forward and Option Contracts [Member] | EUR
Derivative [Line Items]
Notional amounts at January 1	$ 310,000,000	€ 275,000,000	[1]						354,000,000	284,000,000
New contracts	192,000,000	171,000,000	[1]						224,000,000	198,000,000
Matured or expired contracts	(85,000,000)	(75,000,000)	[1]						(311,000,000)	(254,000,000)
Notional amounts at June 30	$ 417,000,000	€ 371,000,000	[1]						$ 267,000,000	€ 228,000,000
Weighted average forward rate at June 30 | € / $	1.13	1.13		1.13		1.13		1.13
Active contracts at June 30	25	25		25		25		25
Forward and Option Contracts [Member] | USD [Member]
Derivative [Line Items]
Notional amounts at January 1 | $	$ 50,000,000
New contracts | $	15,000,000
Matured or expired contracts | $	(15,000,000)
Notional amounts at June 30 | $	$ 50,000,000
Active contracts at June 30	20	20		20		20		20

[1] During the six months ended June 30, 2016, and 2015, we exercised 15 and 13 option contracts, respectively. We realized gains of $0.2 million and $1.9 million for the three and six months ended June 30, 2016, respectively, and gains of $4.0 million and $6.2 million for the three and six months ended June 30, 2015, respectively, in Foreign Currency and Derivative Gains (Losses), Net.

[2] Included in our British pounds sterling denominated option contracts is one forward contract to sell British pounds sterling and buy euros. This forward has a notional amount of £6.0 million (€8.0 million) and was reported in this table using an exchange rate of $1.45 U.S. dollars to the euro.