Note 10 - Intangible Assets - Risk Characteristics of Loans Being Serviced (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2018 USD ($)
Original Term Thirty Year Fixed Rate [Member]
Loan Principal Balance	$ 284,802
Weighted Average Interest Rate	4.10%
Weighted Average Remaining Term (Month)	25 years 210 days
Number of Loans	2,213
Original Term Fifteen Year Fixed Rate [Member]
Loan Principal Balance	$ 100,131
Weighted Average Interest Rate	3.14%
Weighted Average Remaining Term (Month)	11 years 30 days
Number of Loans	1,026
Adjustable Rate [Member]
Loan Principal Balance	$ 54
Weighted Average Interest Rate	4.38%
Weighted Average Remaining Term (Month)	22 years 330 days
Number of Loans	2