Inventories - Narrative (Details) - USD ($) $ in Millions	9 Months Ended
Nov. 03, 2018	Feb. 03, 2018	Jan. 28, 2017
Inventory [Line Items]
Inventory reserves	$ 89.0	$ 40.6	$ 43.0
Signet Path to Brillance
Inventory [Line Items]
Inventory charges	$ 63.2

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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