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Revenue Recognition - Additional Information (Details) - USD ($)
3 Months Ended 9 Months Ended
Sep. 30, 2019
Sep. 30, 2019
Dec. 31, 2018
Disaggregation of Revenue [Abstract]      
Bad debt expense $ 0 $ 0  
Allowance for uncollectible accounts $ 0 $ 0 $ 0