Note 7 - Loans (Details) - Aging of Troubled Debt Restructings - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Financing Receivable, Modifications [Line Items]
Troubled debt restructurings, curent & past due less than 30 days	$ 663,818	$ 630,545
Troubled debt restructurings, nonaccrual	12,060	12,610
Financing Receivables, 1 to 29 Days Past Due [Member]
Financing Receivable, Modifications [Line Items]
Troubled debt restructurings, curent & past due less than 30 days	652,311	614,930
Financing Receivables, 30 to 89 Days Past Due [Member]
Financing Receivable, Modifications [Line Items]
Troubled debt restructurings, curent & past due less than 30 days	4,472	7,490
Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Financing Receivable, Modifications [Line Items]
Troubled debt restructurings, curent & past due less than 30 days	7,035	8,125
Troubled Debt Restructuring [Member]
Financing Receivable, Modifications [Line Items]
Troubled debt restructurings, curent & past due less than 30 days	6,335	7,195
Troubled debt restructurings, nonaccrual	5,216	5,388
Troubled Debt Restructuring [Member] | Financing Receivables, 1 to 29 Days Past Due [Member]
Financing Receivable, Modifications [Line Items]
Troubled debt restructurings, curent & past due less than 30 days	1,013	1,725
Troubled Debt Restructuring [Member] | Financing Receivables, 30 to 89 Days Past Due [Member]
Financing Receivable, Modifications [Line Items]
Troubled debt restructurings, curent & past due less than 30 days	81	82
Troubled Debt Restructuring [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Financing Receivable, Modifications [Line Items]
Troubled debt restructurings, curent & past due less than 30 days	$ 25	$ 0