Commitments and Contingencies - Additional Information (Detail) (USD $)	3 Months Ended		6 Months Ended			1 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013	Aug. 31, 2013 Bellevue Washington [Member]
Other Commitments [Line Items]
Expirations of operating leases			2020
Expiration date of operating lease						2014-08
Amended expiration date of operating lease						2020-05
Rent expense	$ 313,000	$ 378,000	$ 637,000	$ 754,000
Collateral for a bank letter of credit	250,000		250,000		250,000
Volume pricing agreements period of OVRP			12 months
Provision on contingencies	$ 0		$ 0