Derivative Instruments and Hedging Activities - Schedule of Effects of Master Netting Agreements on Consolidated Balance Sheets (Detail) - Cash Flow Hedges [Member] - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Other Current Assets [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gross Amount	$ 37.9	$ 14.5
Offset	9.6	13.4
Net Amount in Balance Sheet	28.3	1.1
Other Assets [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gross Amount	20.9	4.8
Offset	3.5	4.3
Net Amount in Balance Sheet	17.4	0.5
Other Current Liabilities [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gross Amount	9.9	45.8
Offset	9.6	13.4
Net Amount in Balance Sheet	0.3	32.4
Other Long-term Liabilities [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gross Amount	3.7	22.8
Offset	3.5	4.3
Net Amount in Balance Sheet	$ 0.2	$ 18.5