Note 5 - Loans Receivable - Loans Receivable (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Loans receivable, total	$ 1,672,859	$ 1,555,904
Unearned discounts and net deferred loan costs	378	485
Allowance for loan and lease losses	(18,992)	(15,584)	$ (14,550)	$ (13,660)
Loans receivable—net	1,654,245	1,540,805
Real Estate Portfolio Segment [Member] \| One-to-Four-Family Residential [Member]
Loans receivable, total	391,225	389,107
Allowance for loan and lease losses	(4,244)	(3,896)	(3,870)	(4,488)
Real Estate Portfolio Segment [Member] \| Multifamily Residential [Member]
Loans receivable, total	89,087	92,460
Allowance for loan and lease losses	(1,027)	(962)	(665)	(791)
Real Estate Portfolio Segment [Member] \| Nonfarm Nonresidential [Member]
Loans receivable, total	557,185	495,173
Allowance for loan and lease losses	(4,426)	(3,210)	(3,599)	(4,243)
Real Estate Portfolio Segment [Member] \| Farmland [Member]
Loans receivable, total	96,786	94,018
Allowance for loan and lease losses	(1,106)	(863)	(714)	(342)
Real Estate Portfolio Segment [Member] \| Construction Loans [Member]
Loans receivable, total	157,453	125,785
Allowance for loan and lease losses	(2,315)	(1,791)	(1,456)	(1,023)
Commercial Portfolio Segment [Member]
Loans receivable, total	345,087	323,096
Allowance for loan and lease losses	(4,881)	(3,909)	(2,565)	(2,315)
Consumer Portfolio Segment [Member]
Loans receivable, total	36,036	36,265
Allowance for loan and lease losses	$ (556)	$ (360)	$ (166)	$ (101)

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount of deferred interest and fee income, unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of acquired loans. Excludes amounts for loans and leases covered under loss sharing agreements.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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