Share-Based Compensation - Summary of Status of Company's Non-Vested Employee Stock Option Shares (Detail) - $ / shares	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Common Stock Award [Member]
Schedule Of Nonvested Stock Option Activity [Line Items]
Number of shares, Granted	282,509	177,607
Employee Stock Option [Member]
Schedule Of Nonvested Stock Option Activity [Line Items]
Number of shares, Beginning Balance	1,233,184
Number of shares, Granted	2,304,000
Number of shares, Vested	(454,400)
Number of shares, Forfeited	(1,924,000)
Number of shares, Ending Balance	1,158,784	1,233,184
Weighted average grant date fair value, Beginning Balance	$ 0.11
Weighted average grant date fair value, Granted	0.07	$ 0.91
Weighted average grant date fair value, Vested	0.14
Weighted average grant date fair value, Forfeited	0.07
Weighted average grant date fair value, Ending Balance	$ 0.08	$ 0.11
Non Employee Stock Options [Member]
Schedule Of Nonvested Stock Option Activity [Line Items]
Number of shares, Granted	0	416,000
Number of shares, Ending Balance	288,000