Summary of Outstanding Warrants Issued (Detail) (USD $)	0 Months Ended	1 Months Ended	9 Months Ended
	Aug. 14, 2013	Nov. 30, 2010	Sep. 30, 2014
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Line Items]
Warrants Outstanding			963,917
Warrant exercise price	$ 10.00	$ 26.50	$ 30.00
Consultant Warrant
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Line Items]
Warrants Outstanding			85,000
Warrant exercise price			$ 10.70
Issue Date			Aug. 13, 2014
Warrant expiration date			Aug. 13, 2019
Opus Warrant
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Line Items]
Warrants Outstanding			100,000
Warrant exercise price			$ 9.90
Issue Date			Mar. 31, 2014
Warrant expiration date			Mar. 31, 2019
Two Thousand And Thirteen Private Placement Warrant
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Line Items]
Warrants Outstanding			310,540
Warrant exercise price			$ 10.00
Issue Date			Aug. 14, 2013
Warrant expiration date			Aug. 14, 2017
Hercules Warrants
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Line Items]
Warrants Outstanding			99,208
Warrant exercise price			$ 7.10
Issue Date			Aug. 07, 2013
Warrant expiration date			Aug. 07, 2018
Two Thousand And Ten Private Placement Warrant
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Line Items]
Warrants Outstanding			369,169
Warrant exercise price			$ 26.50
Issue Date			Nov. 14, 2010
Warrant expiration date			Nov. 14, 2015