Quarterly report pursuant to Section 13 or 15(d)

Revenue - Schedule of Contract Liabilities (Details)

v3.21.2
Revenue - Schedule of Contract Liabilities (Details) - USD ($)
$ in Thousands
9 Months Ended 12 Months Ended
Sep. 30, 2021
Dec. 31, 2020
Contract with Customer, Liability [Roll Forward]    
Balance, beginning of period $ 8,281 $ 7,244
Deduction for recognition of revenue (5,308) (25,047)
Increase for deferral of shortfall payments 4,338 25,436
Increase for deferral of customer prepayments 187 648
Balance, end of period $ 7,498 $ 8,281