Fair Value Measurements - Fair Value of Assets Required to be Measured at Fair Value (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
Items Measured at Fair Value on a Non-recurring Basis
Total Adjustments Loss/(Gain) - Intangible and Tangible Assets	$ 32.9	$ 104.7	$ 65.8	$ 124.7
Fair Value, Measurements, Nonrecurring [Member]
Items Measured at Fair Value on a Non-recurring Basis
Intangible and tangible assets	295.4		295.4
Total Adjustments Loss/(Gain) - Intangible and Tangible Assets			32.9
Contingent earnout liabilities	70.2		70.2
Total Adjustments Loss/(Gain) - Contingent Earnout Liabilities			32.6
Fair Value, Measurements, Nonrecurring [Member] | Level 1 [Member]
Items Measured at Fair Value on a Non-recurring Basis
Intangible and tangible assets	0		0
Contingent earnout liabilities	0		0
Fair Value, Measurements, Nonrecurring [Member] | Level 2 [Member]
Items Measured at Fair Value on a Non-recurring Basis
Intangible and tangible assets	0		0
Contingent earnout liabilities	0		0
Fair Value, Measurements, Nonrecurring [Member] | Level 3 [Member]
Items Measured at Fair Value on a Non-recurring Basis
Intangible and tangible assets	295.4		295.4
Contingent earnout liabilities	$ 70.2		$ 70.2