Note 2 - Revenue Recognition 2 (Details Textual) - Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-10-01 $ in Millions	Sep. 30, 2020 USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period (Month)	1 year
Revenue, Remaining Performance Obligation, Amount	$ 48.5
Minimum [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period (Month)	1 year 30 days
Maximum [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period (Month)	5 years
Long-term Contract with Customer [Member]
Revenue, Remaining Performance Obligation, Amount	$ 10.7