Fair Value - Reconciliation of Beginning and Ending Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Beginning balance	$ 730,543	$ 44,120
Issuance of warrants	741,828
Change in convertible preferred stock warrant valuation	239,683	388,936
Ending balance		730,543
Series E Convertible Preferred Stock Warrants
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Issuance of warrants		2,190,708
Exercise of warrants	(4,116)	(1,889,201)
Series D Convertible Preferred Stock Warrants
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Exercise of warrants	(91,798)	$ (4,020)
Convertible Note Warrants
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Reclassification of warrants	(1,386,035)
Series C-2 Convertible Preferred Stock Warrants
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Reclassification of warrants	(555)
Growth Term Loan
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Reclassification of warrants	$ (229,550)