Quarterly report pursuant to Section 13 or 15(d)

Fair Value Measurements - Additional Information (Details)

v3.7.0.1
Fair Value Measurements - Additional Information (Details) - USD ($)
1 Months Ended 3 Months Ended 6 Months Ended
Jun. 30, 2017
Jun. 30, 2017
Jun. 30, 2016
Jun. 30, 2017
Jun. 30, 2016
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]          
Loss on remeasurement of convertible preferred stock warrant liability   $ 3,725,000 $ 551,000 $ 3,725,000 $ 551,000
Reclassification of convertible preferred stock warrant liability into additional paid-in capital $ 5,700,000     5,711,000  
Transfers into or out of level 3   $ 0   0  
Other Expense, Net          
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]          
Loss on remeasurement of convertible preferred stock warrant liability $ 3,700,000     $ 3,700,000