Supplemental Cash Flow Information - Changes In Operating Assets And Liabilities, Net of Acquisitions (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Jan. 01, 2017	Jan. 03, 2016
Supplemental Cash Flow Elements [Abstract]
Increase in trade accounts receivable	$ (126.2)	$ (93.9)	$ (64.2)
Increase in prepaid expenses and other assets	(13.8)	(11.0)	(5.2)
Increase in accounts payable and accrued liabilities	63.9	58.4	50.9
Increase (decrease) in accrued payroll and related taxes	32.9	1.9	(23.7)
Increase (decrease) in accrued insurance	6.7	2.4	(4.2)
Increase in income and other taxes	7.1	2.2	0.5
Total changes in operating assets and liabilities, net of acquisition	$ (29.4)	$ (40.0)	$ (45.9)	[1]

[1] Fiscal year included 53 weeks.