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Weichai Transactions (Details) - USD ($)	1 Months Ended
Weichai Transactions (Details) - USD ($)	Nov. 30, 2017	Mar. 31, 2017	Dec. 10, 2021	Jul. 14, 2021	Mar. 26, 2021	Dec. 31, 2020
Revolving credit facility \| First Shareholder's Loan Agreement, Weichai
Subsidiary, Sale of Stock [Line Items]
Maximum borrowing capacity					$ 130,000,000	$ 130,000,000
Revolving credit facility \| Second Shareholder's Loan Agreement, Weichai
Subsidiary, Sale of Stock [Line Items]
Maximum borrowing capacity				$ 25,000,000
Revolving credit facility \| Third Shareholder's Loan Agreement, Weichai
Subsidiary, Sale of Stock [Line Items]
Maximum borrowing capacity			$ 50,000,000
Share Purchase Agreement, Weichai Transaction
Subsidiary, Sale of Stock [Line Items]
Consideration received on transaction		$ 60,000,000.0
Share Purchase Agreement, Weichai Transaction \| Common Stock
Subsidiary, Sale of Stock [Line Items]
Number of shares issued in transaction (in shares)		2,728,752
Share Purchase Agreement, Weichai Transaction \| Redeemable Convertible Series B Preferred Stock
Subsidiary, Sale of Stock [Line Items]
Number of shares issued in transaction (in shares)		2,385,624
Issuance of redeemable convertible Series B Preferred Stock, net of fees (in shares)	4,771,248