Assumptions Used In Binomial Valuation Model and Black-Scholes Valuation Model (Detail)	12 Months Ended	3 Months Ended
	Dec. 31, 2009	Mar. 31, 2014 Black Scholes Option Pricing Model	Mar. 31, 2013 Black Scholes Option Pricing Model	Mar. 31, 2014 Black Scholes Option Pricing Model Minimum	Mar. 31, 2013 Black Scholes Option Pricing Model Minimum
Class of Warrant or Right [Line Items]
Risk-free interest rate	2.14%	0.11%	0.25%
Expected volatility	105.00%	80.00%	70.00%
Expected dividend yield	0.00%	0.00%	0.00%
Expected life in years	5 years	13 years	12 years	8 months 9 days	1 year 8 months 9 days