Quarterly report pursuant to Section 13 or 15(d)

Fair Value Measurements - Rollforward (Details)

v3.19.1
Fair Value Measurements - Rollforward (Details) - USD ($)
$ in Thousands
3 Months Ended
Mar. 31, 2019
Mar. 31, 2018
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Change in fair value $ 289 $ (387)
Fair value, measurements, recurring    
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Balance at December 31, 2018 2,798  
Balance at March 31, 2019 3,087  
Fair value, measurements, recurring | Significant Unobservable Inputs (Level 3)    
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Balance at December 31, 2018 2,798  
Change in fair value 289  
Balance at March 31, 2019 $ 3,087