Note 1 - Summary of Significant Accounting Policies (Details Textual) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2023 USD ($) shares	Jun. 30, 2022 USD ($) shares	Jun. 30, 2023 USD ($) shares	Jun. 30, 2022 USD ($) shares	Dec. 31, 2022 USD ($)
Number of Unconsolidated Business Trusts Formed to Issue Trust Preferred Securities	5		5
Debt Securities, Available-for-Sale, Allowance for Credit Loss	$ 0		$ 0		$ 0
Financing Receivable, Unamortized Loan Cost (Fee)	$ (2,200)		(2,200)		(1,000)
Interest Income on Commercial and Mortgage Loans Discontinued Period (Day)	90 days
Maximum Delinquency Period for Consumer and Credit Card Loans to be Charged Off (Day)	120 days
Loan, Mortgage, Held-for-Sale, Fair Value Disclosure	$ 12,200		12,200		3,600
Financing Receivable, Credit Loss, Expense (Reversal)	2,000	$ 500	2,600	$ 600
Accounts Receivable, Allowance for Credit Loss, Period Increase (Decrease)			(700)
Continuing Involvement with Transferred Financial Assets, Principal Amount Outstanding	$ 1,370,000		$ 1,370,000		1,380,000
Goodwill, Impairment Loss					$ 0
Core Deposits [Member]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life (Year)	10 years
Restricted Stock [Member]
Incremental Common Shares Attributable to Participating Nonvested Shares with Non-forfeitable Dividend Rights (in shares) | shares	350,000	325,000	350,000	325,000
Share-Based Payment Arrangement, Option [Member]
Incremental Common Shares Attributable to Participating Nonvested Shares with Non-forfeitable Dividend Rights (in shares) | shares		1,000		1,000
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount (in shares) | shares	5,000	6,000	5,000	6,000