Condensed Consolidated Balance Sheets (Current Period Unaudited) (Parentheticals) - USD ($) $ / shares in Thousands, $ in Thousands	Jun. 30, 2025	Dec. 31, 2024
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss	$ 1,112,166	$ 1,114,961
Debt Securities, Held-to-Maturity, Fair Value	$ 187,271	$ 341,357
Preferred Stock, No Par Value (in dollars per share)	$ 0	$ 0
Preferred Stock, No Par Value (in dollars per share)	$ 0	$ 0
Preferred Stock, Shares Authorized (in shares)	1,000,000	1,000,000
Preferred Stock, Shares Authorized (in shares)	1,000,000	1,000,000
Preferred Stock, Shares Issued (in shares)	0	0
Preferred Stock, Shares Issued (in shares)	0	0
Preferred Stock, Shares Outstanding (in shares)	0	0
Common Stock, No Par Value (in dollars per share)	$ 0	$ 0
Common Stock, Shares Authorized (in shares)	40,000,000	40,000,000
Common Stock, Shares, Issued (in shares)	29,473,000	29,431,000
Common Stock, Shares, Outstanding (in shares)	29,473,000	29,431,000