Note 7 - Loans - Troubled Debt Restructuring Activity (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Charge-offs
Accruing Troubled Debt Restructuring [Member]
Restructured loans restored to accrual status				10,303
Payments	(1,100)	(1,505)	(5,695)	(3,316)
Restructured loans placed on non-accrual status		(1,138)	(5,822)	(1,138)
Expiration of loan concession upon renewal		(14,886)	(2,240)	(14,886)
Ending balance	79,819	74,708	79,819	74,708
Beginning balance	80,419	90,172	65,393	81,680
New restructurings	500	2,065	28,183	2,065
Non-accruing Troubled Debt Restructuring [Member]
Restructured loans restored to accrual status		1,138	5,822	1,138
Charge-offs	(497)	(945)	(1,546)	(945)
Payments	(2,237)	(1,105)	(3,227)	(7,516)
Foreclosures			(726)
Restructured loans placed on non-accrual status				(10,303)
Ending balance	30,045	25,442	30,045	25,442
Beginning balance	32,779	23,209	29,722	39,923
New restructurings		$ 3,145		$ 3,145