Segment Reporting - Additional Information (Detail) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018 USD ($)	Jul. 01, 2017 USD ($)	Jun. 30, 2018 USD ($) Segment	Jul. 01, 2017 USD ($)
Segment Reporting Information [Line Items]
Operating income (loss)	$ 20.7	$ 16.5	$ 26.8	$ 21.7
Number of reporting segments | Segment			3
Operating Segments | Route Based Services
Segment Reporting Information [Line Items]
Operating income (loss)	27.7	22.9	$ 40.1	32.3
Operating Segments | All Other
Segment Reporting Information [Line Items]
Operating income (loss)	$ (10.2)	(10.4)	$ (20.6)	(20.2)
Adjustments | Operating Segments | Route Based Services
Segment Reporting Information [Line Items]
Operating income (loss)		0.6		0.6
Adjustments | Operating Segments | All Other
Segment Reporting Information [Line Items]
Operating income (loss)		$ (0.6)		$ (0.6)