Note 16 - Estimated Fair Values of Financial Instruments (Details) - USD ($)	Jun. 30, 2016	Dec. 31, 2015
Fair Value, Inputs, Level 1 [Member] | Reported Value Measurement [Member]
Cash and cash equivalents	$ 99,872,000	$ 52,131,000
Federal funds sold	0	18,000
Short term borrowings	14,964,000	12,075,000
Fair Value, Inputs, Level 1 [Member] | Estimate of Fair Value Measurement [Member]
Cash and cash equivalents	99,872,000	52,131,000
Federal funds sold	0	18,000
Short term borrowings	14,964,000	12,075,000
Fair Value, Inputs, Level 2 [Member] | Reported Value Measurement [Member]
Total	1,038,000	0
Interest-bearing time deposits in banks	6,211,000	10,930,000
Other investment securities	11,687,000	9,563,000
Loans held for sale	15,168,000	7,326,000
Cash surrender value of life insurance	56,435,000	52,602,000
Accrued interest receivable	6,166,000	6,157,000
Checking, money market and savings accounts	1,101,357,000	1,094,442,000
Other borrowings	98,182,000	72,380,000
Accrued interest payable	300,000	292,000
Certificates of deposit	6,211,000	10,930,000
Fair Value, Inputs, Level 2 [Member] | Estimate of Fair Value Measurement [Member]
Total	1,038,000	0
Interest-bearing time deposits in banks	6,251,000	11,016,000
Other investment securities	11,687,000	9,563,000
Loans held for sale	15,168,000	7,326,000
Cash surrender value of life insurance	56,435,000	52,602,000
Accrued interest receivable	6,166,000	6,157,000
Checking, money market and savings accounts	1,101,357,000	1,094,442,000
Other borrowings	99,861,000	73,335,000
Accrued interest payable	300,000	292,000
Certificates of deposit	6,251,000	11,016,000
Fair Value, Inputs, Level 3 [Member] | Reported Value Measurement [Member]
Interest-bearing time deposits in banks	539,893,000	513,241,000
Loans receivable—net	1,468,638,000	1,444,102,000
Certificates of deposit	539,893,000	513,241,000
Fair Value, Inputs, Level 3 [Member] | Estimate of Fair Value Measurement [Member]
Interest-bearing time deposits in banks	543,824,000	512,430,000
Loans receivable—net	1,497,525,000	1,462,669,000
Certificates of deposit	543,824,000	$ 512,430,000
Total	$ 1,038,000