Fair Value Measurements-non-recurring (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Apr. 29, 2017	Apr. 30, 2016	Jan. 28, 2017
Fair value measurements
Impairment charge	$ 70	$ 168
Fair Value, Measurements, Nonrecurring
Fair value measurements
Carrying value	70		$ 877
Impairment charge	70		786
Fair Value, Measurements, Nonrecurring \| Level 3
Fair value measurements
Fair value measured using Level 3 inputs	$ 0		$ 91

Represents the carrying amount of long-lived assets which are held and used for normal operations of business and not for sale.

No definition available.

+ Details

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- Definition

Represents the fair value of long-lived assets which are held and used for normal operations of business and not for sale.

+ References

No definition available.

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

The charge against earnings resulting from the aggregate write down of tangible assets from their carrying value to their fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84176398&loc=d3e2921-110230

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=64827811&loc=d3e1361-107760

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