Note 23 - Commitments and Contingent Liabilities - Material Adverse Effect on Company's Financial Condition (Details) $ in Thousands	Dec. 31, 2021 USD ($)
Standby Letters of Credit [Member]
Total Amounts Committed	$ 191,047
Less Than 1 Year	160,488
1-3 Years	30,559
3-5 Years	0
Beyond 5 years	0
Standby Letters of Credit [Member] | Employee Related Commitment [Member]
Total Amounts Committed	58,747
Less Than 1 Year	52,397
1-3 Years	6,350
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	131,902
Less Than 1 Year	107,693
1-3 Years	24,209
3-5 Years	0
Beyond 5 years	0
Surety Bond [Member]
Total Amounts Committed	622,866
Less Than 1 Year	583,311
1-3 Years	39,555
3-5 Years	0
Beyond 5 years	0
Surety Bond [Member] | Employee Related Commitment [Member]
Total Amounts Committed	81,524
Less Than 1 Year	80,224
1-3 Years	1,300
3-5 Years	0
Beyond 5 years	0
Surety Bond [Member] | Environmental Commitment [Member]
Total Amounts Committed	537,015
Less Than 1 Year	498,909
1-3 Years	38,106
3-5 Years	0
Beyond 5 years	0
Surety Bond [Member] | Other Commitment [Member]
Total Amounts Committed	4,327
Less Than 1 Year	4,178
1-3 Years	149
3-5 Years	0
Beyond 5 years	0
Other Guarantee Obligations [Member] | Other Commitment [Member]
Total Amounts Committed	1,156
Less Than 1 Year	1,156
1-3 Years	0
3-5 Years	0
Beyond 5 years	$ 0