Preferred Stock, Common Stock and Stockholders' Equity - Summary of Nonvested Options Activity (Detail) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Number of Shares [Roll Forward]
Shares Nonvested , Outstanding beginning balance	534,210
Shares, Granted	64,000
Shares Vested	(173,791)
Shares Nonvested , Outstanding ending balance	424,419	534,210
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Weighted Average Grant Date Fair Value Per Share, Nonvested beginning balance	$ 8.84
Weighted Average Grant Date Fair Value Per Share, Granted	$ 4.76	$ 6.33
Weighted Average Grant Date Fair Value Per Share, Vested	$ 7.96
Weighted Average Grant Date Fair Value Per Share, Nonvested ending balance	$ 9.02	$ 8.84