Note 8 - Leases - Lease Modifications (Details) - USD ($) $ in Thousands			6 Months Ended	9 Months Ended
	Aug. 16, 2021	Sep. 22, 2020	Jun. 30, 2021	Sep. 30, 2021	Sep. 30, 2020
Execution of lease for facility in Fremont, California			$ 1,176
Lease Facility in Fremont, California [Member]
Execution of lease for facility in Fremont, California	$ 202			$ 202
Lease Agreement, EMS Facility in Fremont, California [Member]
Modification to lease for facility					$ 1,176
Lease Agreement, EMS Facility in Mt. Laurel, New Jersey [Member]
Execution of lease for facility in Fremont, California		$ 2,051
Modification to lease for facility					$ 2,051