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Note 9 - Debt (Details Textual) - USD ($) $ in Millions	1 Months Ended	3 Months Ended
Note 9 - Debt (Details Textual) - USD ($) $ in Millions	Sep. 30, 2021	Sep. 30, 2021	Jun. 30, 2021	Dec. 31, 2021	Jun. 30, 2020
Line of Credit Facility, Maximum Borrowing Capacity					$ 100.0
Line of Credit Facility, Remaining Borrowing Capacity	$ 75.0	$ 75.0
Minimum [Member]
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage		0.15%
Maximum [Member]
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage		0.25%
Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate [Member]
Debt Instrument, Basis Spread on Variable Rate		0.50%
London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument, Basis Spread on Variable Rate		1.00%	2.00%
London Interbank Offered Rate (LIBOR) [Member] \| Minimum [Member]
Debt Instrument, Basis Spread on Variable Rate		1.00%
London Interbank Offered Rate (LIBOR) [Member] \| Maximum [Member]
Debt Instrument, Basis Spread on Variable Rate		2.25%
Base Rate [Member] \| Minimum [Member]
Debt Instrument, Basis Spread on Variable Rate		0.00%
Base Rate [Member] \| Maximum [Member]
Debt Instrument, Basis Spread on Variable Rate		1.25%
Revolving Credit Facility [Member]
Line of Credit Facility, Maximum Borrowing Capacity	75.0	$ 75.0
Line of Credit Facility, Remaining Borrowing Capacity				$ 13.4
Term Loan [Member]
Debt Instrument, Face Amount	25.0	25.0
Debt Instrument, Annual Principal Payment	$ 3.6	$ 3.6
Debt Instrument, Term (Year)	5 years