Business Segments, Significant Customer and Geographic Information - Reconciliation of Total Segment (Details) - USD ($)	12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Segment income (loss):
Operating income (loss)	$ (5,976,000)	$ (7,959,000)	$ (5,602,000)
Amortization of intangible assets	(757,000)	(275,000)	(88,000)
Operating segments
Segment income (loss):
Operating income (loss)	14,491,000	7,894,000	9,416,000
Unallocated amounts
Segment income (loss):
Corporate expenses	(19,710,000)	(15,578,000)	(14,930,000)
Amortization of intangible assets	$ (757,000)	$ (275,000)	$ (88,000)