Retirement plans - Fair Value Measurements of Plan Assets (Details) - Foreign Plan - Pension plan - USD ($) $ in Millions	Jan. 29, 2022	Jan. 30, 2021	Feb. 01, 2020
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 295.6	$ 299.2	$ 281.9
Fair Value, Inputs, Level 1, 2 and 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	295.6	278.7
Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	4.0	209.5
Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	69.2
Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	291.6	0.0
Diversified equity securities | Fair Value, Inputs, Level 1, 2 and 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	13.0
Diversified equity securities | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
Diversified equity securities | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	13.0
Diversified equity securities | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0
Diversified growth funds | Fair Value, Inputs, Level 1, 2 and 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	44.4
Diversified growth funds | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	44.4
Diversified growth funds | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
Diversified growth funds | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0
Fixed income – government bonds | Fair Value, Inputs, Level 1, 2 and 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	161.4
Fixed income – government bonds | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	161.4
Fixed income – government bonds | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
Fixed income – government bonds | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0
Corporate bonds and notes | Fair Value, Inputs, Level 1, 2 and 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	56.2
Corporate bonds and notes | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
Corporate bonds and notes | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	56.2
Corporate bonds and notes | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0
Insurance contracts | Fair Value, Inputs, Level 1, 2 and 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	291.6	0.0
Insurance contracts | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
Insurance contracts | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
Insurance contracts | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	291.6
Cash | Fair Value, Inputs, Level 1, 2 and 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	4.0	3.7
Cash | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	4.0	3.7
Cash | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
Cash | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0
Fixed income | NAV
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	18.0
Property | NAV
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 0.0	$ 2.5