Revenue Recognition - Additional Information (Details 1) $ in Thousands	Jun. 30, 2019 USD ($)
Revenue Recognition [Line Items]
Estimated revenue expected to be recognized in the future	$ 3,626
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2019-07-01
Revenue Recognition [Line Items]
Estimated revenue expected to be recognized in the future	$ 980
Revenue, remaining performance obligation, expected timing of satisfaction, period	6 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2020-01-01
Revenue Recognition [Line Items]
Estimated revenue expected to be recognized in the future	$ 1,639
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2021-01-01
Revenue Recognition [Line Items]
Estimated revenue expected to be recognized in the future	$ 1,004
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2022-01-01
Revenue Recognition [Line Items]
Estimated revenue expected to be recognized in the future	$ 3
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year