Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Aug. 01, 2021	Aug. 02, 2020	Aug. 01, 2021	Aug. 02, 2020
Statement of Comprehensive Income [Abstract]
Net income	$ 9.5	$ 18.1	$ 36.9	$ 14.9
Net interest rate swap gain (loss), net of tax (expense) benefit of $(0.9), $(0.3), $(1.2) and $0.1	4.7	1.6	6.6	(0.8)
Total comprehensive income	14.2	$ 19.7	43.5	$ 14.1
Less: comprehensive loss attributable to non-controlling interests	(15.7)		(15.7)
Total comprehensive income attributable to Core & Main, Inc.	$ 29.9		$ 59.2