Note 4 - Loans/Leases Receivable - Concentration by Industries (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Loans and Leases Receivable, Gross	$ 4,251,129	$ 3,690,205
Lessors of Non-residential Buildings [Member]
Loans and Leases Receivable, Gross	$ 591,398	$ 574,058
Percentage of total loans/leases	14.00%	17.00%
Lessors of Residential Buildings [Member]
Loans and Leases Receivable, Gross	$ 1,134,178	$ 745,770
Percentage of total loans/leases	27.00%	22.00%
Administration of Urban Planning and Community and Rural Development [Member]
Loans and Leases Receivable, Gross	$ 138,514	$ 133,157
Percentage of total loans/leases	3.00%	4.00%