Revenue, Properties and Outsourcing Assets by Geographic Segment (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	$ 764.8	$ 806.4	$ 1,486.0	$ 1,568.1
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	383.9	308.4	725.9	619.7
United Kingdom
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	83.6	126.6	171.5	222.9
Other International
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	$ 297.3	$ 371.4	$ 588.6	$ 725.5