Note 4 - Derivative and Other Hedging Instruments - Open Payer Swap Positions (Details)	Mar. 31, 2023	Dec. 31, 2022
Receive index, percent	100.00%	100.00%
Overnight SOFR Index Rate [Member]
Receive index, percent	58.00%	50.00%
Three Month LIBOR Index Rate [Member]
Receive index, percent	42.00%	50.00%