Schedule II - Valuation And Qualifying Accounts (Details) - Allowance for doubtful accounts and other sales allowances - USD ($)	12 Months Ended
Jan. 31, 2016	Jan. 25, 2015	Jan. 26, 2014
Change in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Year	$ 3,523,148	$ 3,824,676	$ 4,917,070
Reversal to Costs and Expenses			(567,394)
Charged to Costs and Expenses	5,154,545	396,151
Deductions	(884,894)	(697,679)	(525,000)
Balance at End of Year	$ 7,792,799	$ 3,523,148	$ 3,824,676

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

Total of allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 09
-Article 12

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- Definition

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- Definition

Total of the deductions in a given period to allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs, representing receivables written off as uncollectible and portions of the reserves utilized, respectively.

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- Definition

Total of recoveries of amounts due the Entity that had previously been written off as uncollectible using allowances (the valuation accounts that are netted against the cost of an asset to value it at its carrying value) and total of reestablishments of reserves (liabilities established to represent expected future costs) that had previously been utilized.

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