Note 7 - Fair Value of Financial Instruments (Details) - Fair Values of Financial Instruments - USD ($) $ in Thousands	Sep. 30, 2015	Jun. 30, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Dec. 31, 2013
Financial assets:
Cash and cash equivalents	$ 110,519		$ 128,826
Cash and cash equivalents, at fair value	110,519		128,826
Investment securities available for sale	209,119		185,379
Investment securities available for sale, at fair value	209,119		185,379
Investment securities held to maturity	140,116		67,866
Investment securities held to maturity, at fair value	141,519		68,253
Restricted stock, at cost	1,179		1,157
Restricted stock, at fair value	1,179		1,157
Loans held for sale	489		1,676
Loans held for sale, at fair value	489		1,699
Loans receivable, net	837,037		770,404
Loans receivable, net, at fair value	826,195		760,163
SBA servicing assets	4,174		4,099
SBA servicing assets, at fair value	4,174	$ 4,319	4,099	$ 4,040	$ 4,067	$ 3,477
Accrued interest receivable	3,548		3,226
Accrued interest receivable, at fair value	3,548		3,226
Deposits
Demand, savings and money market	1,162,426		996,861
Demand, savings and money market, at fair value	1,162,426		996,861
Time deposits	75,070		75,369
Time deposits, at fair value	75,180		75,592
Subordinated debt	22,476		22,476
Subordinated debt	19,490		18,221
Accrued interest payable	283		265
Accrued interest payable, at fair value	283		265
Off-Balance Sheet Data
Commitments to extend credit	0		0
Commitments to extend credit, at fair value	0		0
Standby letters-of-credit	0		0
Standby letters-of-credit, at fair value	0		0
Fair Value, Inputs, Level 1 [Member]
Financial assets:
Cash and cash equivalents, at fair value	110,519		128,826
Investment securities available for sale	0		0
Investment securities available for sale, at fair value	0		0
Investment securities held to maturity, at fair value	0		0
Restricted stock, at fair value	0		0
Loans held for sale, at fair value	0		0
Loans receivable, net, at fair value	0		0
SBA servicing assets, at fair value	0		0
Accrued interest receivable, at fair value	0		0
Deposits
Demand, savings and money market, at fair value	0		0
Time deposits, at fair value	0		0
Subordinated debt	0		0
Accrued interest payable, at fair value	0		0
Fair Value, Inputs, Level 2 [Member]
Financial assets:
Cash and cash equivalents, at fair value	0		0
Investment securities available for sale	204,748		179,181
Investment securities available for sale, at fair value	204,748		179,181
Investment securities held to maturity, at fair value	141,519		68,253
Restricted stock, at fair value	1,179		1,157
Loans held for sale, at fair value	0		0
Loans receivable, net, at fair value	0		0
SBA servicing assets, at fair value	0		0
Accrued interest receivable, at fair value	3,548		3,226
Deposits
Demand, savings and money market, at fair value	1,162,426		996,861
Time deposits, at fair value	75,180		75,592
Subordinated debt	0		0
Accrued interest payable, at fair value	283		265
Fair Value, Inputs, Level 3 [Member]
Financial assets:
Cash and cash equivalents, at fair value	0		0
Investment securities available for sale	4,371		6,198
Investment securities available for sale, at fair value	4,371		6,198
Investment securities held to maturity, at fair value	0		0
Restricted stock, at fair value	0		0
Loans held for sale, at fair value	489		1,699
Loans receivable, net, at fair value	826,195		760,163
SBA servicing assets, at fair value	4,174		4,099
Accrued interest receivable, at fair value	0		0
Deposits
Demand, savings and money market, at fair value	0		0
Time deposits, at fair value	0		0
Subordinated debt	19,490		18,221
Accrued interest payable, at fair value	$ 0		$ 0