Including the current and noncurrent portions, carrying value as of the balance sheet date of a written promise to pay a note, initially due after one year or beyond the operating cycle if longer, which can be exchanged for a specified amount of one or more securities (typically common stock), at the option of the issuer or the holder.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.16)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16(a))

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 16

-Article 9

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 20, 22

-Article 5

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

Net Loss Per Share - Schedule of Anti-dilutive Securities Excluded from Computation of Diluted Net Loss Per Share (Parenthetical) (Detail) (USD $)	1 Months Ended
	Jun. 30, 2013	Apr. 30, 2013	Oct. 31, 2012	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2012
Earnings Per Share [Abstract]
Contingently convertible notes payable					$ 41,860,000	$ 8,804,000
Warrants issued to purchase a percentage of common stock	10.00%	15.00%	15.00%
Value of common stock in a sale of the Company or an initial public offering	70.00%		70.00%
Percentage of exercise price on the value of common stock	70.00%		70.00%