Revenue recognition - ESP and Voucher Promotions (Details) - USD ($) $ in Millions	May 04, 2019	Feb. 02, 2019	May 05, 2018
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Total deferred revenue	$ 976.6	$ 966.5	$ 952.4
Deferred revenue	277.0	270.0	284.9
Non-current liabilities	699.6	696.5	667.5
ESP deferred revenue
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Total deferred revenue	931.3	927.6	913.5
Voucher promotions and other
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Total deferred revenue	$ 45.3	$ 38.9	$ 38.9

Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as noncurrent.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130549-203045

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82913815&loc=SL49130532-203044

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=82913815&loc=SL49130531-203044

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