Acquired Intangible Assets and Related Amortization (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Finite Lived Intangible Assets [Line Items]
Acquired intangible assets, net	$ 221.6	$ 226.5
Client relationships
Finite Lived Intangible Assets [Line Items]
Acquired intangible assets, gross	237.4	219.6
Accumulated amortization	(86.6)	(74.0)
Acquired intangible assets, net	150.8	145.6
Trade secrets
Finite Lived Intangible Assets [Line Items]
Acquired intangible assets, gross	31.1	31.4
Accumulated amortization	(18.5)	(16.0)
Acquired intangible assets, net	12.6	15.4
Software
Finite Lived Intangible Assets [Line Items]
Acquired intangible assets, gross	71.0	73.2
Accumulated amortization	(38.8)	(33.7)
Acquired intangible assets, net	32.2	39.5
Trade names
Finite Lived Intangible Assets [Line Items]
Acquired intangible assets, gross	31.3	28.3
Accumulated amortization	(11.7)	(10.3)
Acquired intangible assets, net	19.6	18.0
Other Intangible Assets
Finite Lived Intangible Assets [Line Items]
Acquired intangible assets, gross	26.1	24.9
Accumulated amortization	(19.7)	(16.9)
Acquired intangible assets, net	$ 6.4	$ 8.0