Organization and summary of significant accoutning policies - Property Plant and Equipment (Details)	12 Months Ended
	Feb. 03, 2018
Minimum | Buildings
Property, Plant and Equipment [Line Items]
Useful life	30 years
Minimum | Furniture and fixtures
Property, Plant and Equipment [Line Items]
Useful life	3 years
Minimum | Equipment, including software
Property, Plant and Equipment [Line Items]
Useful life	3 years
Maximum | Buildings
Property, Plant and Equipment [Line Items]
Useful life	40 years
Maximum | Leasehold Improvements
Property, Plant and Equipment [Line Items]
Useful life	10 years
Maximum | Furniture and fixtures
Property, Plant and Equipment [Line Items]
Useful life	10 years
Maximum | Equipment, including software
Property, Plant and Equipment [Line Items]
Useful life	5 years