Note 4 - Loans/Leases Receivable - Concentration by Industries (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Loans and Leases Receivable, Gross	$ 3,690,205	$ 3,732,754
Lessors of Non-residential Buildings [Member]
Loans and Leases Receivable, Gross	$ 574,058	$ 632,534
Percentage of total loans/leases	17.00%	17.00%
Lessors of Residential Buildings [Member]
Loans and Leases Receivable, Gross	$ 745,770	$ 594,346
Percentage of total loans/leases	22.00%	16.00%
Administration of Urban Planning and Community and Rural Development [Member]
Loans and Leases Receivable, Gross	$ 133,157	$ 111,579
Percentage of total loans/leases	4.00%	3.00%
Bank Holding Companies [Member]
Loans and Leases Receivable, Gross	$ 92,185	$ 75,601
Percentage of total loans/leases	3.00%	2.00%