Note 6 - Loans and Allowance for Credit Losses (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024		Dec. 31, 2023		Dec. 31, 2022	Dec. 21, 2024	Dec. 31, 2021
Financing Receivable, Unamortized Loan Cost (Fee)	$ 1,100		$ 200
Interest Receivable	20,075		15,700
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	3,992,534		2,759,583
Off-Balance-Sheet, Credit Loss, Liability, Credit Loss Expense (Reversal)	(81,000)		2,200
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, Credit Loss Expense (Reversal)	133		40
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest	59,929		35,843		$ 31,146		$ 31,572
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Period Increase (Decrease)	$ 24,100
Percentage of Increase in Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest	67.20%
Financing Receivable, Excluding Accrued Interest, Credit Loss Expense (Reversal)	$ 18,089	[1]	(225)	[2]	0
Loans and Leases Receivables, Impaired, Troubled Debt, Interest Income	4,800		500		200
Financing Receivable, Nonaccrual, Interest Income	0		0		$ 0
Financing Receivable, Excluding Accrued Interest, Modified in Period, Amount			0
Financing Receivable, Excluding Accrued Interest, Modified, Subsequent Default	0		0
Financial Asset, Past Due [Member]
Financing Receivable, Excluding Accrued Interest, Modified in Period, Amount	0		0
Financial Asset Acquired with Credit Deterioration [Member]
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest	10,200
Financing Receivable, Excluding Accrued Interest, Credit Loss Expense (Reversal)	7,300
Asset Pledged as Collateral [Member] | FHLB Borrowings, Deposits, and Other [Member]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	2,900		1,600
Loans Receivable [Member]
Interest Receivable	$ 16,400		12,200
Metro Phoenix Bank and HMN Financial Inc. [Member]
Financing Receivable, Unamortized Purchase Premium (Discount)			$ 5,100			$ 70,600

[1] The difference in the credit loss expense reported herein compared to the consolidated statements of income is associated with the credit loss expense of ($81) million related to off-balance sheet credit exposure and $133 thousand related to investment securities held-to-maturity.

[2] The difference in the credit loss expense reported herein compared to the consolidated statements of income is associated with the credit loss expense of $44 thousand related to off-balance sheet credit exposure and $46 thousand related to HTM investment securities.