Warrant Exercise (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013
Class of Warrant or Right [Line Items]
Cash Received	$ 3,700	$ 201
Equity Warrants
Class of Warrant or Right [Line Items]
Warrant exercised	2,292,362	98,359
Common Stock Issued
Class of Warrant or Right [Line Items]
Warrant exercised	1,991,409	98,359
Cash exercises
Class of Warrant or Right [Line Items]
Cash Received	$ 3,700	$ 201
Cash exercises | Equity Warrants
Class of Warrant or Right [Line Items]
Warrant exercised	1,813,707	98,359
Cash exercises | Common Stock Issued
Class of Warrant or Right [Line Items]
Warrant exercised	1,813,707	98,359
Cashless Exercise | Equity Warrants
Class of Warrant or Right [Line Items]
Warrant exercised	478,655
Cashless Exercise | Common Stock Issued
Class of Warrant or Right [Line Items]
Warrant exercised	177,702