Short-Term Borrowings - Additional Information (Details) - Revolving Credit Facility $ in Thousands	12 Months Ended
Jan. 31, 2017 USD ($)
Line of Credit Facility
Termination date for senior, unsecured revolving credit facility	Jan. 09, 2020
Revolving credit facility, maximum borrowing capacity	$ 125,000
Percentage of net current account receivable included in cash and account receivable ratio	42.00%
Maximum amount available for dividends and stock repurchase dollar limit	$ 200,000
Maximum amount available for dividend distribution and stock repurchase percent of cumulative net income (loss)	70.00%
Minimum
Line of Credit Facility
Commitment fee percentage on unused line of credit	0.30%
Adjusted quick ratio	1.00
Cash and accounts receivable ratio	1.25
Minimum \| L I B O R
Line of Credit Facility
Basis spread on variable rate	2.00%
Minimum \| Base Rate
Line of Credit Facility
Basis spread on variable rate	1.00%
Maximum
Line of Credit Facility
Commitment fee percentage on unused line of credit	0.40%
Leverage ratio	2.00
Senior leverage ratio	0.90
Maximum \| L I B O R
Line of Credit Facility
Basis spread on variable rate	2.50%
Maximum \| Base Rate
Line of Credit Facility
Basis spread on variable rate	1.50%

Adjusted Quick Ratio under the covenants of the credit facility.

No definition available.

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- Definition

The percentage of our cumulative net income added to the dollar limitation under the revolving credit facility, for which we may declare dividends or repurchase our stock.

+ References

No definition available.

+ Details

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- Definition

Cash And Accounts Receivable Ratio under the covenants of the credit facility.

+ References

No definition available.

+ Details

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- Definition

Leverage Ratio under the covenants of the credit facility.

+ References

No definition available.

+ Details

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- Definition

Amount added to the percent of cumulative net income to calculate the limit for which we may declare dividends or purchase our stock under the covenants of the credit facility.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Percentage of Net Current Account Receivable Included in Cash and Account Receivable Ratio under the covenants of the credit facility.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Senior Leverage Ratio under covenants of the credit facility.

+ References

No definition available.

+ Details

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Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Date the credit facility terminates, in CCYY-MM-DD format.

+ References

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 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ 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.

+ Details

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

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- Details

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- Details

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- Details

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- Details

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- Details

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