Fair Value Measurements - Additional Information (Detail)	Jan. 31, 2014 USD ($) $ / shares
Fair Value Disclosure [Line Items]
Purchase of warrants to common stock \| $	$ 23,858
Class of Warrant or Right, Exercise Price of Warrants or Rights	$ 30.40
Adjusted Exercise Price Of Warrants	$ 22.70

Exercise price per share or per unit of warrants or rights outstanding.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(i)(4))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant