Significant Accounting Policies - Summary of Changes in Common Stock Warrant Liability and Contingent Consideration Liability (Details) - USD ($) $ in Thousands |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2016 |
Dec. 31, 2015 |
Dec. 31, 2014 |
|
| Contingent Consideration | |||
| Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] | |||
| Fair value, beginning balance | $ 4,867 | $ 4,826 | $ 5,607 |
| Change in fair value | 371 | 41 | (781) |
| Fair value, ending balance | 5,238 | 4,867 | 4,826 |
| Common Stock Warrant Liability | |||
| Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] | |||
| Fair value, beginning balance | 5,500 | 5,080 | 1,380 |
| Change in fair value | 5,880 | 420 | 3,700 |
| Fair value, ending balance | $ 11,380 | $ 5,500 | $ 5,080 |