Other Noncurrent Liabilities - Other Noncurrent Liabilities (Detail) - USD ($) $ in Millions	Jun. 30, 2015	Dec. 31, 2014
Other Liabilities Disclosure [Abstract]
Reserve for uncertain tax positions	$ 29.1	$ 34.1
Asset retirement obligations	28.1	27.2
Deferred income	11.5	18.9
Employee benefits	7.4	8.1
Insurance claims and expenses	9.6	9.5
Deferred payment obligation	8.6	8.5
Accrued workforce reduction costs	2.9
Other	6.7	6.4
Total	$ 103.9	$ 112.7