Financial Instruments and Fair Value Measurements - Foreign Currency Contracts Activity (Detail)	12 Months Ended
	Dec. 31, 2015 USD ($) Derivative $ / € € / $ £ / $ CAD / $ ¥ / $	Dec. 31, 2015 JPY (¥) Derivative $ / € € / $ £ / $ CAD / $ ¥ / $	Dec. 31, 2015 EUR (€) Derivative $ / € € / $ £ / $ CAD / $ ¥ / $	Dec. 31, 2015 CAD Derivative $ / € € / $ £ / $ CAD / $ ¥ / $	Dec. 31, 2015 GBP (£) Derivative $ / € € / $ £ / $ CAD / $ ¥ / $	Dec. 31, 2014 USD ($)	Dec. 31, 2014 JPY (¥)	Dec. 31, 2014 EUR (€)	Dec. 31, 2014 GBP (£)	Dec. 31, 2013 USD ($)	Dec. 31, 2013 JPY (¥)	Dec. 31, 2013 EUR (€)
Derivative [Line Items]
Notional amounts at January 1 | $						$ 333,500,000
Notional amounts at December 31 | $										$ 333,500,000
Net Investment Forward Contracts [Member] | EUR
Derivative [Line Items]
Notional amounts at January 1	$ 400,000,000		€ 300,000,000			800,000,000		€ 600,000,000		1,304,000,000		€ 1,000,000,000
New contracts	0		0			2,354,000,000		1,746,000,000		800,000,000		600,000,000
Matured or expired contracts	(400,000,000)		(300,000,000)			(2,754,000,000)		(2,046,000,000)		(1,304,000,000)		(1,000,000,000)
Notional amounts at December 31	$ 0		€ 0			400,000,000		300,000,000		800,000,000		600,000,000
Weighted average forward rate at December 31 | € / $	0	0	0	0	0
Active contracts at December 31	0	0	0	0	0
Net Investment Forward Contracts [Member] | GBP [Member]
Derivative [Line Items]
Notional amounts at January 1	$ 400,000,000				£ 238,000,000	0			£ 0
New contracts	186,000,000				118,000,000	400,000,000			238,000,000
Matured or expired contracts	(200,000,000)				(118,000,000)	0			0
Notional amounts at December 31	$ 386,000,000				£ 238,000,000	400,000,000			238,000,000	0
Weighted average forward rate at December 31 | £ / $	1.62	1.62	1.62	1.62	1.62
Active contracts at December 31	3	3	3	3	3
Net Investment Forward Contracts [Member] | JPY
Derivative [Line Items]
Notional amounts at January 1	$ 250,000,000	¥ 24,136,000,000				250,000,000	¥ 24,136,000,000			0	¥ 0
New contracts	353,000,000	43,373,000,000				769,000,000	79,010,000,000			250,000,000	24,136,000,000
Matured or expired contracts	(603,000,000)	(67,509,000,000)				(769,000,000)	(79,010,000,000)			0	0
Notional amounts at December 31	$ 0	¥ 0				250,000,000	24,136,000,000			250,000,000	¥ 24,136,000,000
Weighted average forward rate at December 31 | ¥ / $	0	0	0	0	0
Active contracts at December 31	0	0	0	0	0
Net Investment Forward Contracts [Member] | CAD
Derivative [Line Items]
Notional amounts at January 1	$ 0			CAD 0
New contracts	298,000,000			394,000,000
Matured or expired contracts	(298,000,000)			(394,000,000)
Notional amounts at December 31	$ 0			CAD 0		0
Weighted average forward rate at December 31 | CAD / $	0	0	0	0	0
Active contracts at December 31	0	0	0	0	0
Forward and Option Contracts [Member]
Derivative [Line Items]
Notional amounts at December 31			€ 21,500,000		£ 16,000,000
Weighted average forward rate at December 31 | $ / €	1.09	1.09	1.09	1.09	1.09
Forward and Option Contracts [Member] | EUR
Derivative [Line Items]
Notional amounts at January 1	$ 354,000,000		€ 284,000,000			0		0
New contracts	375,000,000		333,000,000			464,000,000		365,000,000
Matured or expired contracts	(419,000,000)		(342,000,000)			(110,000,000)		(81,000,000)
Notional amounts at December 31	$ 310,000,000		€ 275,000,000			354,000,000		€ 284,000,000		$ 0		€ 0
Weighted average forward rate at December 31 | € / $	1.13	1.13	1.13	1.13	1.13
Active contracts at December 31	19	19	19	19	19
Forward and Option Contracts [Member] | GBP [Member]
Derivative [Line Items]
Notional amounts at January 1	$ 0				£ 0
New contracts	300,000,000				199,000,000
Matured or expired contracts	(152,000,000)				(102,000,000)
Notional amounts at December 31	$ 148,000,000				£ 97,000,000	0			£ 0
Weighted average forward rate at December 31 | £ / $	1.31	1.31	1.31	1.31	1.31
Active contracts at December 31	16	16	16	16	16
Forward and Option Contracts [Member] | JPY
Derivative [Line Items]
Notional amounts at January 1	$ 0	¥ 0
New contracts	159,000,000	18,740,000,000
Matured or expired contracts	(50,000,000)	(5,900,000,000)
Notional amounts at December 31	$ 109,000,000	¥ 12,840,000,000				0	¥ 0
Weighted average forward rate at December 31 | ¥ / $	118.23	118.23	118.23	118.23	118.23
Active contracts at December 31	16	16	16	16	16
Forward and Option Contracts [Member] | USD [Member]
Derivative [Line Items]
Notional amounts at January 1 | $	$ 0
New contracts | $	71,000,000
Matured or expired contracts | $	(21,000,000)
Notional amounts at December 31 | $	$ 50,000,000					$ 0
Weighted average forward rate at December 31	0	0	0	0	0
Active contracts at December 31	20	20	20	20	20