Restricted Cash - Additional Information (Detail) (USD $)	6 Months Ended
Jun. 30, 2013	Jan. 31, 2013	Dec. 31, 2012
Restricted Cash and Cash Equivalents Items [Line Items]
Restricted cash	$ 500,000		$ 1,000,000
Convertible secured promissory notes, percentage of principal amount outstanding	66.67%
Warrants issued to purchase common stock	187,500	243,750

Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

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)(2))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph i

-Subparagraph 2

-Article 4

Name:	us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant