Change in Allowance for Doubtful Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
Jan. 31, 2016	Jan. 31, 2015	Jan. 31, 2014
Allowance for doubtful accounts receivable, beginning balance	$ 4,217
Allowance for doubtful accounts receivable, ending balance	3,826	$ 4,217
ment:AllowanceForDoubtfulAccountsAdjustment [Member]
Valuation Allowances and Reserves, Period Increase (Decrease)		(1,691)
Allowance for Doubtful Accounts [Member]
Allowance for doubtful accounts receivable, beginning balance	4,217	5,469	$ 5,331
Valuation Allowances and Reserves, Period Increase (Decrease)	(349)	(988)	517
Valuation Allowances and Reserves, Adjustments	(42)	(264)	(379)
Allowance for doubtful accounts receivable, ending balance	$ 3,826	$ 4,217	$ 5,469

A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.4)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5074-111524

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- Definition

Total of the adjustments 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.

+ 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

Total increases or decreases in 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

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