Summary Of Significant Accounting Policies - Additional Information (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended			124 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2013
Summary Of Significant Accounting Policies [Line Items]
Stock based compensation expenses	$ 3,507	$ 4,880	$ 2,759	$ 23,688
Weighted average fair value of stock option granted	$ 2.51	$ 3.06	$ 4.04
Current Asset | Line of Credit
Summary Of Significant Accounting Policies [Line Items]
Restricted cash	200			200
Other Noncurrent Assets | Lease Obligations
Summary Of Significant Accounting Policies [Line Items]
Restricted cash	409			409
Other Noncurrent Assets | Line of Credit
Summary Of Significant Accounting Policies [Line Items]
Restricted cash	103			103
Minimum
Summary Of Significant Accounting Policies [Line Items]
Property and equipment useful life	3 years
Maximum
Summary Of Significant Accounting Policies [Line Items]
Property and equipment useful life	5 years
Employee Stock Option
Summary Of Significant Accounting Policies [Line Items]
Stock based compensation expenses	2,300	3,100	2,100
Restricted Stock
Summary Of Significant Accounting Policies [Line Items]
Stock based compensation expenses	1,200	1,700	635
Employee and Director Awards
Summary Of Significant Accounting Policies [Line Items]
Stock based compensation expenses	$ 3,500	$ 4,900	$ 2,800