Goodwill and Intangibles - Summary of Goodwill (Details) - USD ($) $ in Millions	12 Months Ended
Feb. 03, 2018	Jan. 28, 2017
Goodwill [Roll Forward]
Beginning balance	$ 517.6	$ 515.5
Impact of foreign exchange	2.4	2.1
Acquisitions	301.7
Ending balance	821.7	517.6
Sterling Jewelers
Goodwill [Roll Forward]
Beginning balance	23.2	23.2
Impact of foreign exchange	0.0	0.0
Acquisitions	301.7
Ending balance	324.9	23.2
Zale Jewelry
Goodwill [Roll Forward]
Beginning balance	490.8	488.7
Impact of foreign exchange	2.4	2.1
Acquisitions	0.0
Ending balance	493.2	490.8
Piercing Pagoda
Goodwill [Roll Forward]
Beginning balance	0.0	0.0
Impact of foreign exchange	0.0	0.0
Acquisitions	0.0
Ending balance	0.0	0.0
UK Jewelry
Goodwill [Roll Forward]
Beginning balance	0.0	0.0
Impact of foreign exchange	0.0	0.0
Acquisitions	0.0
Ending balance	0.0	0.0
Other
Goodwill [Roll Forward]
Beginning balance	3.6	3.6
Impact of foreign exchange	0.0	0.0
Acquisitions	0.0
Ending balance	$ 3.6	$ 3.6

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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