Segment Reporting and Geographic Information - Selected Financial Data for Each of Operating Segments (Detail) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Segment Reporting Information [Line Items]
Revenue	$ 3,342.3	$ 2,362.0	$ 1,215.9	$ 703.0	$ 830.7	$ 662.5	$ 581.0	$ 282.4	$ 7,623.2	$ 2,356.6	$ 702.3
Operating income (loss)	(38.0)	44.3	(30.1)	(4.8)	6.0	(13.6)	(11.9)	(21.4)	(28.6)	(40.9)	(52.3)
Depreciation and amortization									364.9	98.3	20.8
Interest expense	95.9	61.4	36.3	23.1	16.7	17.8	3.4	10.1	216.7	48.0	18.2
Income tax provision (benefit)	(69.6)	$ 1.8	$ (9.5)	$ (13.6)	(0.9)	$ (20.1)	$ (1.8)	$ (3.3)	(90.9)	(26.1)	(22.5)
Goodwill	4,610.6				929.3				4,610.6	929.3	363.4
Capital expenditures									249.0	44.6	11.6
Operating Segments | Transportation
Segment Reporting Information [Line Items]
Revenue									4,924.4	2,140.0	702.3
Operating income (loss)									51.6	18.9	(7.2)
Depreciation and amortization									226.5	79.5	19.7
Interest expense									25.0	0.5	0.0
Income tax provision (benefit)									(10.5)	0.8	(2.4)
Goodwill	2,504.7				577.0				2,504.7	577.0	363.4
Capital expenditures									126.3	13.4	5.3
Operating Segments | Logistics
Segment Reporting Information [Line Items]
Revenue									2,768.4	216.6	0.0
Operating income (loss)									81.6	17.6	0.0
Depreciation and amortization									136.9	16.3	0.0
Interest expense									15.3	0.0	0.0
Income tax provision (benefit)									17.6	0.0	0.0
Goodwill	2,105.9				352.3				2,105.9	352.3	0.0
Capital expenditures									109.5	24.0	0.0
Corporate
Segment Reporting Information [Line Items]
Revenue									0.0	0.0	0.0
Operating income (loss)									(162.0)	(77.4)	(45.1)
Depreciation and amortization									1.5	2.5	1.1
Interest expense									176.4	47.5	18.2
Income tax provision (benefit)									(98.0)	(26.9)	(20.1)
Goodwill	0.0				0.0				0.0	0.0	0.0
Capital expenditures									13.2	7.2	6.3
Eliminations
Segment Reporting Information [Line Items]
Revenue									(69.6)	0.0	0.0
Operating income (loss)									0.2	0.0	0.0
Depreciation and amortization									0.0	0.0	0.0
Interest expense									0.0	0.0	0.0
Income tax provision (benefit)									0.0	0.0	0.0
Goodwill	$ 0.0				$ 0.0				0.0	0.0	0.0
Capital expenditures									$ 0.0	$ 0.0	$ 0.0