Taxes on Earnings (Loss) (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended	9 Months Ended
Nov. 30, 2019	Oct. 31, 2020	Nov. 02, 2019	Oct. 31, 2020	Nov. 02, 2019	Feb. 01, 2020
Income Tax Disclosure [Abstract]
Effective income tax rate (percent)		4.00%	23.00%	45.00%	23.00%
Effective income tax rate, change from prior year (percent)		(0.19)		0.22
Unrecognized tax benefits		$ 76.1	$ 83.4	$ 76.1	$ 83.4	$ 67.1
Income tax penalties and interest accrued		9.4	$ 13.9	9.4	$ 13.9	$ 7.2
Amount recognized by Company related to decrease in reserves for tax positions in prior period, including interest and penalties	$ 16.2
Amount recognized by Company related to decrease in reserves for tax positions in prior period, interest and penalties	$ 6.6
Impact of recognizing taxes and interest related to unrecognized tax benefits		60.6		60.6
Unrecognized tax benefits reduction resulting from conclusion of certain state tax matters or lapse of applicable statute of limitations (up to)		$ 10.1		$ 10.1

Effective Income Tax Rate, Change From Prior Year, Percent

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Unrecognized Tax Benefits, Decrease Resulting From Prior Period Tax Positions, Income Tax Penalties And Interest Accrued

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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The amount of the unrecognized tax benefit of a position taken for which it is reasonably possible that the total amount thereof will significantly increase or decrease within twelve months of the balance sheet date.

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Amount of unrecognized tax benefits.

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Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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