Summary of Significant Accounting Policies (Gain) Loss on the Sale of Trade Receivables (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Jan. 31, 2015	Jan. 31, 2014	Jan. 31, 2013
Sale of Receivables
Total receivables sold	$ 23,176ment_ReceivablesSoldOnNonRecourseBasis	$ 23,617ment_ReceivablesSoldOnNonRecourseBasis	$ 20,711ment_ReceivablesSoldOnNonRecourseBasis
Net proceeds	22,572	22,943	20,198
Discount on sold receivables	(604)ment_DiscountsonSoldReceivables	(674)ment_DiscountsonSoldReceivables	(513)ment_DiscountsonSoldReceivables
Unaccreted interest on sold receivables	922	890	568
Gain on sale of accounts receivable	318	216	55
Trade accounts receivable
Sale of Receivables
Total receivables sold	12,715	11,705	9,617
Term Receivables Long Term
Sale of Receivables
Total receivables sold	$ 10,461	$ 11,912	$ 11,094

The discount recognized during the period on the sale of receivables.

No definition available.

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- Definition

Total receivables sold to financing institutions on a non-recourse basis during the period.

+ References

No definition available.

+ Details

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- Details

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- Definition

The amount of unaccreted interest on sold receivables recognized during the period.

+ References

No definition available.

+ Details

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- Definition

Reflects the net positive or negative amount derived from subtracting from net proceeds of sale, the carrying amounts, net of allocated reserves, of accounts receivable transferred to a third party in a transaction that qualifies for sales treatment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 20

-Section 50

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=13989330&loc=d3e107425-111719

+ Details

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- Definition

The cash inflow associated with the sale of receivables arising from the financing of goods and services.

+ References

No definition available.

+ Details

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