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Contract Assets and Contract Liabilities - Additional Information (Details) - USD ($)
3 Months Ended 6 Months Ended
Jun. 30, 2021
Jun. 30, 2020
Jun. 30, 2021
Jun. 30, 2020
Revenue From Contract With Customer [Abstract]        
Impairment losses on receivables $ 0 $ 0 $ 0 $ 0
Impairment losses on contract assets $ 0 $ 0 $ 0 $ 0