Note 2 - Summary of Significant Accounting Policies - Remaining Performance Obligations (Details)	Mar. 31, 2020 USD ($)
Revenue, Remaining Performance Obligation, Amount	$ 4,156,000
Service [Member]
Revenue, Remaining Performance Obligation, Amount	2,104,000
Clinical Revenue [Member]
Revenue, Remaining Performance Obligation, Amount	218,000
Exclusivity Fee [Member]
Revenue, Remaining Performance Obligation, Amount	$ 1,834,000