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.

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

+ Details

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- Definition

Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.13)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

No definition available.

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Property and Equipment, Net - Additional Information (Detail) (USD $)	12 Months Ended
	Jan. 31, 2015	Jan. 31, 2014	Jan. 31, 2013	Jul. 22, 2014
Property, Plant and Equipment [Line Items]
Depreciation	$ 1,400,000us-gaap_Depreciation	$ 900,000us-gaap_Depreciation	$ 500,000us-gaap_Depreciation
Property and equipment, gross	30,542,000us-gaap_PropertyPlantAndEquipmentGross	3,839,000us-gaap_PropertyPlantAndEquipmentGross
Land and Building [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross				24,000,000
Building [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 20,984,000
Useful life of building	30 years