Revenue from Contracts with Customers - Performance Obligations Unsatisfied at End of Period (Details) $ in Thousands	Dec. 31, 2018 USD ($)
Revenue from Contract with Customer [Abstract]
Performance obligation unsatisfied or partially unsatisfied	$ 1,727
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-01-01
Revenue from Contract with Customer [Abstract]
Performance obligation unsatisfied or partially unsatisfied	$ 759
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Estimated remaining performance period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-01-01
Revenue from Contract with Customer [Abstract]
Performance obligation unsatisfied or partially unsatisfied	$ 369
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Estimated remaining performance period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01
Revenue from Contract with Customer [Abstract]
Performance obligation unsatisfied or partially unsatisfied	$ 303
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Estimated remaining performance period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01
Revenue from Contract with Customer [Abstract]
Performance obligation unsatisfied or partially unsatisfied	$ 153
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Estimated remaining performance period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Revenue from Contract with Customer [Abstract]
Performance obligation unsatisfied or partially unsatisfied	$ 143
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Estimated remaining performance period	1 year