The change in the inventory reserve representing the cumulative difference in cost between the first in, first out and the last in, first out inventory valuation methods, which change has been reflected in the statement of income during the period.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.6b)
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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-Subparagraph (SX 210.5-02.6c)
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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-Subparagraph (SX 210.5-02.6a)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 330
-SubTopic 10
-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=27011343&loc=d3e99989-122729

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Basis of presentation (Details) $ in Thousands		3 Months Ended		9 Months Ended		12 Months Ended
Basis of presentation (Details) $ in Thousands	Feb. 02, 2019 USD ($)	Oct. 30, 2020 USD ($)	Nov. 01, 2019 USD ($)	Oct. 30, 2020 USD ($)	Nov. 01, 2019 USD ($)	Jan. 29, 2021 period	Jan. 31, 2020 period
Fiscal year, number of weeks \| period						52	52
Merchandise inventories
LIFO provision		$ 1,600	$ 3,200	$ 3,300	$ 9,700
New accounting guidance
Adjustment to retained earnings					$ 28,830
Accounting Standards Update 2016-02
New accounting guidance
Adjustment to retained earnings	$ 28,800