Recently Issued Accounting Standards (Details) - USD ($) $ in Millions		May 02, 2020		Aug. 04, 2019	Aug. 03, 2019
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease right-of-use asset		$ 637.6			$ 0.0
Present value of operating lease liabilities	[1],[2]	837.0
Accumulated deficit		(1,656.6)			(935.9)
Prepaid expenses and other current assets		158.5			242.3
Current assets related to discontinued operations		6.1			98.2
Other intangible assets, net		176.0			276.6
Non-current assets related to discontinued operations		0.0			11.5
Current portion of lease liabilities		167.7	[1],[2]		0.0
Current liabilities related to discontinued operations		35.8			94.7
Lease-related liabilities		0.0			204.6
Long-term lease liabilities		669.3	[1],[2]		0.0
Non-current liabilities related to discontinued operations		$ 5.5			35.5
Minimum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Incremental borrowing rate (percent)		24.00%
Maximum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Incremental borrowing rate (percent)		30.00%
Accounting Standards Update 2016-02
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease right-of-use asset		$ 744.4			744.4
Accumulated deficit		(11.5)		$ (11.5)	(947.4)
Prepaid expenses and other current assets		(33.6)			208.7
Current assets related to discontinued operations		(7.6)			90.6
Other intangible assets, net		(8.4)			268.2
Non-current assets related to discontinued operations		131.5			143.0
Current portion of lease liabilities		141.3			141.3
Current liabilities related to discontinued operations		37.8			132.5
Lease-related liabilities		(204.6)			0.0
Long-term lease liabilities		769.1			769.1
Non-current liabilities related to discontinued operations		$ 94.2			$ 129.7

[1] Although such amounts are generally non-cancelable, certain leases are cancelable if specified sales levels are not achieved or co-tenancy requirements are not being satisfied. All future minimum rentals under such leases have been included in the above table.

[2] Net of sublease income, which is not expected to be significant in any period.