Note 5 - Mortgage Servicing Rights - Fair Value of Servicing Rights (Details) - Mortgage Servicing Rights [Member]	Jun. 30, 2023	Dec. 31, 2022
Measurement Input, Discount Rate [Member]
Valuation assumptions	0.12	0.12
Measurement Input, Prepayment Rate [Member] | Minimum [Member]
Valuation assumptions	1.01	1.16
Measurement Input, Prepayment Rate [Member] | Maximum [Member]
Valuation assumptions	5.99	2.10
Measurement Input, Weighted Average Prepayment Rate [Member]
Valuation assumptions	1.14	1.31