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Revenue - Narrative (Details) - USD ($)
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Revenue from Contract with Customer [Abstract]    
Increase (decrease) in deferred revenue $ 0  
Deferred revenue   $ 1,100,000
Contract with customer, liability, revenue recognized 1,100,000 900,000
Contract assets $ 0 $ 0