Inventories (Details) - USD ($) $ in Millions	9 Months Ended
May 02, 2020	Aug. 03, 2019	May 04, 2019
Inventory [Line Items]
Total inventories	$ 449.7	$ 490.7	$ 559.3
Premium Fashion
Inventory [Line Items]
Total inventories	280.5	226.3	286.6
Plus Fashion
Inventory [Line Items]
Total inventories	103.5	156.5	181.5
Kids Fashion
Inventory [Line Items]
Total inventories	65.7	$ 107.9	$ 91.2
Plus Fashion and Kids Fashion
Inventory [Line Items]
Inventory write-down	$ 135.0

Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of merchandise or goods held by the company that are readily available for sale.

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Amount of loss from reductions in inventory due to subsequent measurement adjustments, including, but not limited to, physical deterioration, obsolescence, or changes in price levels.

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