Revenue Recognition - Performance Obligation (Details) $ in Millions	Jan. 01, 2019 USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-01-01
Revenue from Contract with Customer [Abstract]
Performance obligation	$ 0.1
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Performance obligation, 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	$ 0.1
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Performance obligation, 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	$ 0.1
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Performance obligation, 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	$ 0.1
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Performance obligation, 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	$ 0.8
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Performance obligation, period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: (nil)
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Performance obligation, period