Note 12 - Commitments and Contingent Liabilities - Material Adverse Effect on Company's Financial Condition (Details) $ in Thousands	Sep. 30, 2022 USD ($)
Standby Letters of Credit [Member]
Total Amounts Committed	$ 188,290
Less Than 1 Year	149,740
1-3 Years	38,550
3-5 Years	0
Beyond 5 years	0
Standby Letters of Credit [Member] | Employee Related Commitment [Member]
Total Amounts Committed	51,739
Less Than 1 Year	31,023
1-3 Years	20,716
3-5 Years	0
Beyond 5 years	0
Standby Letters of Credit [Member] | Environmental Commitment [Member]
Total Amounts Committed	398
Less Than 1 Year	398
1-3 Years	0
3-5 Years	0
Beyond 5 years	0
Standby Letters of Credit [Member] | Other Commitment [Member]
Total Amounts Committed	136,153
Less Than 1 Year	118,319
1-3 Years	17,834
3-5 Years	0
Beyond 5 years	0
Surety Bond [Member]
Total Amounts Committed	613,354
Less Than 1 Year	558,456
1-3 Years	54,898
3-5 Years	0
Beyond 5 years	0
Surety Bond [Member] | Employee Related Commitment [Member]
Total Amounts Committed	81,524
Less Than 1 Year	48,024
1-3 Years	33,500
3-5 Years	0
Beyond 5 years	0
Surety Bond [Member] | Environmental Commitment [Member]
Total Amounts Committed	527,426
Less Than 1 Year	506,233
1-3 Years	21,193
3-5 Years	0
Beyond 5 years	0
Surety Bond [Member] | Other Commitment [Member]
Total Amounts Committed	4,404
Less Than 1 Year	4,199
1-3 Years	205
3-5 Years	0
Beyond 5 years	$ 0