Note Payable and Accrued Expenses - Additional Information (Details) - Oxford $ in Millions	12 Months Ended	15 Months Ended
	Dec. 31, 2016 USD ($) installment	Dec. 31, 2015 USD ($)
Debt Instrument
Borrowing capacity under the loan & security agreement		$ 3.0
Minimum interest rate		7.50%
Number of debt instrument payments | installment	36
Final payment of additional interest as a percentage of aggregate amount advanced	5.70%
Weighted average annual effective interest rate	11.10%
Minimum prepayment fee interest rate percentage	1.00%
Maximum prepayment fee interest rate percentage	3.00%
Advance received under loan and security agreement	$ 0.9
Outstanding loan balance, default interest rate	5.00%
Three months US LIBOR
Debt Instrument
Basis spread on fixed interest rate set at time of advance		7.27%