Basis of Presentation - Schedule of Revision of Balance Sheet (Detail) - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017	Mar. 31, 2017
Error Corrections And Prior Period Adjustments Restatement [Line Items]
Receivables, less allowance for doubtful accounts	$ 1,345.4	$ 1,417.6	$ 1,244.1
Inventories	339.9	416.8	382.4
Accounts payable	$ 860.8	$ 1,094.7	866.5
As Reported
Error Corrections And Prior Period Adjustments Restatement [Line Items]
Receivables, less allowance for doubtful accounts			1,268.9
Inventories			375.9
Accounts payable			884.8
Adjustments
Error Corrections And Prior Period Adjustments Restatement [Line Items]
Receivables, less allowance for doubtful accounts			(24.8)
Inventories			6.5
Accounts payable			$ (18.3)