Property and Equipment - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Jan. 31, 2014	Jan. 31, 2013	Jan. 31, 2012
Property Plant And Equipment [Abstract]
Depreciation expense	$ 1,834	$ 1,626	$ 1,438
Cost of equipment held pursuant to capital leases	16,802	14,450
Accumulated amortization	$ 10,997	$ 9,752

The aggregate amount of recurring noncash expense charged against earnings in the period to allocate the cost of assets over their estimated remaining economic lives.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

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- Definition

Amount before accumulated depreciation of leased physical assets used in the normal conduct of business to produce goods and services.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 30

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6455314&loc=d3e45014-112735

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- Definition

The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

+ References

+ Details

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Balance Type:	debit
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- Details

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