Accounts receivable, net - Portfolio of Accounts Receivable (Details) - USD ($) $ in Millions	Jul. 30, 2016	Jan. 30, 2016	Aug. 01, 2015
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable, net	$ 1,650.6	$ 1,756.4	$ 1,493.2
Consumer Portfolio Segment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable, net	1,615.6		1,483.1
Other Accounts Receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable, net	10.0	16.9	10.1
Sterling Jewelers | Consumer Portfolio Segment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable, net	1,615.6	1,725.9	1,483.1
Zale Jewelry | Consumer Portfolio Segment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable, net	$ 25.0	$ 13.6	$ 0.0