Fair Value Measures - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2021	Dec. 31, 2020	Oct. 04, 2021	Mar. 31, 2021
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Number of common stock shares converted per preferred share (in shares)					3,120,000
Interest expense	$ 187	$ 191	$ 611	$ 571
Changes in fair value of promissory note	0	973	605	(1,394)
Yaskawa Note
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Accrued interest on promissory note	0		0			$ 523
Interest expense	3	38	77	113
Changes in fair value of promissory note		$ (973)	(605)	$ 1,400
Yaskawa Note | Yaskawa
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Principal and unpaid interest of convertible note					$ 15,600
Principal amount of long term loan facility	15,000		15,000
Accrued interest on promissory note	$ 600		$ 600
Number of common stock shares converted per preferred share (in shares)					3,120,000