Note 15 - Income Taxes - Net Operating Loss Carry Forwards and Tax Credit Carry Forwards Available to Offset Future Federal Income Tax (Details) $ in Thousands	Mar. 31, 2020 USD ($)
Operating Loss Carryforwards, Total	$ 14,961
Tax Credit Carryforward, Amount	28
Expiration Tax Year 2022 [Member]
Operating Loss Carryforwards, Total	2,839
Tax Credit Carryforward, Amount
Expiration Tax Year 2023 [Member]
Operating Loss Carryforwards, Total	1,863
Tax Credit Carryforward, Amount
Expiration Tax Year 2025 [Member]
Operating Loss Carryforwards, Total
Tax Credit Carryforward, Amount	8
Expiration Tax Year 2026 [Member]
Operating Loss Carryforwards, Total	159
Tax Credit Carryforward, Amount	2
Expiration Tax Year 2027 [Member]
Operating Loss Carryforwards, Total	2,665
Tax Credit Carryforward, Amount
ExpirationTax Year 2028 [Member]
Operating Loss Carryforwards, Total	1,612
Tax Credit Carryforward, Amount	1
Expiration Tax Year 2031 [Member]
Operating Loss Carryforwards, Total	389
Tax Credit Carryforward, Amount
Expiration Tax Year 2032 [Member]
Operating Loss Carryforwards, Total	44
Tax Credit Carryforward, Amount	1
Expiration Tax Year 2033 [Member]
Operating Loss Carryforwards, Total	76
Tax Credit Carryforward, Amount	16
Expiration Tax Year 2034 [Member]
Operating Loss Carryforwards, Total	392
Tax Credit Carryforward, Amount
Expiration Tax Year 2035 [Member]
Operating Loss Carryforwards, Total	18
Tax Credit Carryforward, Amount
Expiration Tax Year 2037 [Member]
Operating Loss Carryforwards, Total	1,680
Tax Credit Carryforward, Amount
Expiration Tax Year 2038 [Member]
Operating Loss Carryforwards, Total	168
Tax Credit Carryforward, Amount
Expiration Tax Year 2039 [Member]
Operating Loss Carryforwards, Total	3,056
Tax Credit Carryforward, Amount