Accrued Expenses - Additional Information (Details) - USD ($)	3 Months Ended	12 Months Ended
	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014
Accrued Expenses [Line Items]
Accrued severance			$ 179,000
Separation Agreement 1
Accrued Expenses [Line Items]
Severance expense	$ 300,000
Payment out of severance accrual			300,000
Accrued severance		$ 0	45,890
Separation Agreement 2
Accrued Expenses [Line Items]
Severance expense		300,000	100,000
Accrued severance		$ 0	$ 100,000
Severance agreement description		In August 2014, the Company entered into a separation agreement with an employee, which became effective on August 13, 2014. The Company will record the expense and liability associated with the separation agreement ratably over the period from August 5, 2014 through December 31, 2015 because the severance payments are subject to continued service and forfeiture until December 31, 2015. During the year ended 2015 and 2014, the Company recorded severance expense in the amount of approximately $0.3 million and $0.1 million respectively, which was recorded to research and development expense. At December 31, 2015 and 2014, approximately $0 and $0.1 million, respectively, remained in accrued expense in relation to the unpaid severance costs.