Organization and principal accounting policies - Narrative (Details)	3 Months Ended		12 Months Ended	3 Months Ended
	May 02, 2015 Segment	May 03, 2014	Jan. 31, 2015	Jan. 30, 2016	Oct. 31, 2015	Aug. 01, 2015
Property, Plant and Equipment [Line Items]
Number of reportable segments	5
Organization and critical accounting policies [Abstract]
Percent of annual sales	20.00%
Minimum
Organization and critical accounting policies [Abstract]
Operating income expected in fourth quarter	45.00%
Maximum
Organization and critical accounting policies [Abstract]
Operating income expected in fourth quarter	55.00%
Sterling Jewelers | Minimum
Organization and critical accounting policies [Abstract]
Operating income expected in fourth quarter	40.00%
Sterling Jewelers | Maximum
Organization and critical accounting policies [Abstract]
Operating income expected in fourth quarter	45.00%
Theft Protection | Zale
Revenue Recognition [Abstract]
Product warranty	2 years
Lifetime Warranty | Sterling Jewelers
Revenue Recognition [Abstract]
Deferred revenue recognition period of extended service plan sales	14 years
Revenue recognized percentage In relation to costs expected to be incurred within first two years	43.00%	45.00%	45.00%
Revenue recognized in relation to costs expected to be incurred period	2 years
Lifetime Warranty | Zale
Revenue Recognition [Abstract]
Revenue recognized percentage In relation to costs expected to be incurred within first two years	69.00%		69.00%
Product warranty	10 years
Watch Warranty | Zale
Revenue Recognition [Abstract]
Product warranty	2 years
Breakage Warranty | Zale
Revenue Recognition [Abstract]
Product warranty	1 year
Breakage Warranty | Piercing Pagoda
Revenue Recognition [Abstract]
Product warranty	1 year
Jewelry Replacement Plan | Sterling Jewelers
Revenue Recognition [Abstract]
Deferred revenue recognition period of extended service plan sales	3 years
Forecast
Organization and critical accounting policies [Abstract]
Percent of annual sales				40.00%	20.00%	20.00%