Financial Instruments - Net Investment Hedge Derivative Instruments on OCI (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Derivative Instruments Gain Loss [Line Items]
Amount of Gain (Loss) Recognized in OCI on Derivatives (Effective Portion)	$ (0.8)	$ 0.8	$ 0	$ 1.4
Amount of Gain (Loss) Reclassified from Accumulated OCI (Effective Portion)	0	0	0	0
Euro-denominated [Member]
Derivative Instruments Gain Loss [Line Items]
Amount of Gain (Loss) Recognized in OCI on Derivatives (Effective Portion)	0	(0.1)	0	0.1
Amount of Gain (Loss) Reclassified from Accumulated OCI (Effective Portion)	0	0	0	0
Canadian dollar-denominated [Member]
Derivative Instruments Gain Loss [Line Items]
Amount of Gain (Loss) Recognized in OCI on Derivatives (Effective Portion)	(0.8)	0.9	0	1.3
Amount of Gain (Loss) Reclassified from Accumulated OCI (Effective Portion)	$ 0	$ 0	$ 0	$ 0