Income Taxes - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Income Taxes [Line Items]
Effective income tax rate	25.90%	29.70%	27.80%	33.40%
Increase/(decrease) in effective tax rate due to impact of discrete tax items	1.20%	4.30%	0.20%	(0.70%)
Net increase to income tax reserves for unrecognized tax benefits based on tax positions related to current and prior years			$ 2.3
Decrease to income tax reserves for unrecognized tax benefits of prior years due to lapse of applicable statute of limitations			0.5
Unrecognized tax benefits reserve that would impact effective tax rate if released into income	$ 32.9		32.9
Current Tax Payable
Income Taxes [Line Items]
Unrecognized tax benefits reserve that would impact effective tax rate if released into income	10.8		10.8
Non-Current Tax Payable
Income Taxes [Line Items]
Unrecognized tax benefits reserve that would impact effective tax rate if released into income	$ 22.1		$ 22.1