Retirement plans - Change in UK Plan Assets (Details) - USD ($) $ in Millions	12 Months Ended
Feb. 01, 2020	Feb. 02, 2019
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value at beginning of year	$ 33.9
Fair value at end of year	27.5	$ 33.9
Pension plan \| Foreign Plan
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value at beginning of year	245.5	272.2
Actual return on UK Plan assets	36.8	2.1
Employer contributions	5.3	4.4
Members’ contributions	0.2	0.3
Benefits paid	(9.4)	(13.5)
Foreign currency translation	3.5	(20.0)
Fair value at end of year	$ 281.9	$ 245.5

Amount of increase (decrease) in plan assets of defined benefit plan from actual return (loss) determined by change in fair value of plan assets adjusted for contributions, benefit payments, and other expenses.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Amount of contribution received by defined benefit plan from employer which increases plan assets.

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- Definition

Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee.

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- Definition

Amount of payment to participant under defined benefit plan which decreases plan assets. For pension plan, payment includes, but is not limited to, pension benefits and death benefits. For other postretirement plan, payment includes, but is not limited to, prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services.

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- Definition

Amount of contributions received by defined benefit plan from participant which increases plan assets.

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- Definition

Amount of foreign currency translation gain (loss) which increases (decreases) plan assets of defined benefit plan.

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