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Borrowings - 2018 Term Loan (Details) - USD ($)		9 Months Ended
Borrowings - 2018 Term Loan (Details) - USD ($)	Sep. 28, 2018	Sep. 30, 2020	Dec. 31, 2019	Sep. 30, 2019
Debt Instrument [Line Items]
Non-current restricted cash		$ 3,441,000	$ 3,867,000	$ 4,300,000
Term loan \| 2018 Term Loan
Debt Instrument [Line Items]
Debt term (in years)	3 years
Principal amount	$ 60,000,000.0
Non-current restricted cash		3,400,000
Minimum aggregate principal payment		5,000,000.0
Borrowings principal repayment (Note 9)		1,000,000.0
Fair value of term loan		$ 58,400,000