Financial Instruments and Fair Value Measurements - Derivative Activity (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Derivative [Line Items]
Acquired contracts		$ 71.0
Matured or expired contracts	(319.9)
Foreign Currency Forwards [Member]
Derivative [Line Items]
Notional amounts at January 1	1,303.8
Matured or expired contracts	(663.7)
Notional amounts at March 31	640.1
Interest Rate Swaps [Member]
Derivative [Line Items]
Notional amounts at January 1	1,314.8	1,496.5
New contracts		367.0
Acquired contracts		71.0
Matured or expired contracts	(1,230.2)	(393.3)
Notional amounts at March 31	84.6	1,541.2
Interest Rate Caps [Member]
Derivative [Line Items]
New contracts		194.1
Notional amounts at March 31		$ 194.1