Quarterly report pursuant to Section 13 or 15(d)

Revenue from Contracts with Customers - Summary of Future Obligations (Details)

v3.10.0.1
Revenue from Contracts with Customers - Summary of Future Obligations (Details)
$ in Thousands
 6 Months Ended
Jun. 30, 2018
USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2018-07-01  
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]  
Deferred revenue $ 1,403
Revenue, remaining performance obligation, expected timing of satisfaction, period 6 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-01-01  
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]  
Deferred revenue $ 515
Revenue, remaining performance obligation, expected timing of satisfaction, period 1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-01-01  
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]  
Deferred revenue $ 239
Revenue, remaining performance obligation, expected timing of satisfaction, period 1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01  
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]  
Deferred revenue $ 2,738
Revenue, remaining performance obligation, expected timing of satisfaction, period