Pension Plans - Changes in Fair Value of Level 3 Investment Assets (Details) - USD ($) $ in Millions	12 Months Ended
	Feb. 03, 2018	Jan. 28, 2017
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value at beginning of year	$ 37.1
Fair value at end of year	37.5	$ 37.1
Significant Unobservable inputs (Level 3)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value at beginning of year	11.8	13.0
Actual return on assets	2.5	(1.2)
Fair value at end of year	$ 14.3	$ 11.8