Debts - Notes payable (Details) - Yaskawa Note - USD ($) $ in Thousands	Dec. 31, 2021	Oct. 31, 2021	Sep. 30, 2021	Mar. 31, 2021	Oct. 31, 2017
Line of Credit Facility [Line Items]
Interest rate per annum	1.00%				1.00%
Unsecured subordinated convertible promissory note	$ 0	$ 15,600	$ 15,000	$ 15,523	$ 15,000
Promissory note	$ 0			$ 16,128

Including the current and noncurrent portions, the carrying value of convertible subordinated debt, as of the balance sheet date, initially scheduled to be repaid after one year or beyond the normal operating cycle if longer. This form of debt can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder, and places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets.

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Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Fair value portion of notes payable.

+ References

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