Stockholders' Equity - Schedule of Outstanding Common Stock Warrants (Detail)	6 Months Ended
	Jun. 30, 2014
Class of Warrant or Right [Line Items]
Total Warrants	2,084,767
Ex. Price $ 11.18 [Member]
Class of Warrant or Right [Line Items]
Issue Date	Apr. 26, 2013
Expiration Date	Apr. 26, 2018
Total Warrants	69,321
Ex. Price	11.18
Ex. Price $ 8.50 [Member]
Class of Warrant or Right [Line Items]
Issue Date	Oct. 31, 2013
Expiration Date	Oct. 31, 2018
Total Warrants	685,715
Ex. Price	8.50
Ex. Price $ 7.40 [Member]
Class of Warrant or Right [Line Items]
Issue Date	Feb. 05, 2014
Expiration Date	Feb. 05, 2019
Total Warrants	1,329,731
Ex. Price	7.40