Related Party Transactions - Additional Information (Details) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013
Related Party Transaction [Line Items]
Research and development service expenses	$ 60,000	$ 64,000	$ 120,000	$ 126,000
Accounts payable	$ 20,000		$ 20,000		$ 18,000