Debts - Additional Information (Details)			1 Months Ended	3 Months Ended
	Jul. 16, 2021 USD ($)	Feb. 12, 2020 USD ($) shares $ / shares	Dec. 31, 2020 USD ($)	Jun. 30, 2021 USD ($)	Mar. 31, 2021 USD ($)	Jun. 30, 2020 USD ($)	May 18, 2021 USD ($)	Mar. 01, 2021 USD ($)	Dec. 31, 2019 USD ($)	Jul. 31, 2019 USD ($)	Mar. 31, 2019 USD ($)	Apr. 04, 2018 USD ($)	Oct. 31, 2017 USD ($)
Line of Credit Facility [Line Items]
Aggregate principal amount of loans outstanding				$ 35,914,000
Interest expense accrued				38,000	$ 37,000	$ 37,000
Outstanding balance on line of credit facility					10,200,000
Maximum number of shares of common stock issuable (in shares) | shares		3,076,171
Conversion price per share on convertible note payable (in dollars per share) | $ / shares		$ 5.12
Interest Expense				204,000		189,000
Term of cooperation and development agreement.			3 years
Deferred revenue				1,016,000	505,000
Accounts Payable and Accrued Liabilities
Line of Credit Facility [Line Items]
Interest Expense				150,000		0
Yaskawa
Line of Credit Facility [Line Items]
Letter of intent for development activities		$ 4,000,000.0	$ 4,000,000.0
Proceeds from collaborators			$ 1,000,000.0
Deferred revenue				750,000		0
Loan and Security Agreement (LSA)
Line of Credit Facility [Line Items]
Long-term loan facility												$ 15,000,000.0
Aggregate principal amount of loans outstanding				8,000,000.0	10,000,000.0
Tranche A Loan
Line of Credit Facility [Line Items]
Long-term loan facility												5,000,000.0
Tranche B Loan
Line of Credit Facility [Line Items]
Long-term loan facility								$ 10,000,000		$ 8,000,000.0	$ 8,000,000	10,000,000
Tranche B Loan | Subsequent Event
Line of Credit Facility [Line Items]
Repayment of Nexperia debt	$ 8,000,000.0
Tranche B-1 Loan
Line of Credit Facility [Line Items]
Long-term loan facility				12,200,000			$ 2,000,000		$ 2,000,000.0		$ 2,000,000
Tranche B-1 Loan | Subsequent Event
Line of Credit Facility [Line Items]
Repayment of Nexperia debt	$ 8,000,000
Tranche C Note
Line of Credit Facility [Line Items]
Long-term loan facility												12,000,000.0
Revolving loan												$ 10,000,000.0
Interest rate per annum												6.00%
Interest expense accrued				$ 166,000		152,000
Yaskawa Note
Line of Credit Facility [Line Items]
Interest rate per annum				1.00%									1.00%
Unsecured subordinated convertible promissory note				$ 15,561,000	15,523,000								$ 15,000,000.0
Maximum number of shares of common stock issuable (in shares) | shares		3,076,171
Interest Expense				37,000		$ 38,000
Accrued interest on promissory note				$ 561,000	$ 523,000