Note 7 - Loans and the Allowance for Loan Losses - Loans Receivable (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Loans	$ 1,528,469	$ 975,284
Allowance for loan losses	(11,220)	(8,765)	$ (8,162)
Net loans	1,517,249	966,519
Commercial Real Estate Portfolio Segment [Member] \| Construction and Land [Member]
Loans	211,054	143,535
Allowance for loan losses	(1,590)	(1,421)	(933)
Commercial Real Estate Portfolio Segment [Member] \| Farmland [Member]
Loans	45,989	10,480
Allowance for loan losses	(104)	(76)	(75)
Commercial Real Estate Portfolio Segment [Member] \| Nonfarm Nonresidential [Member]
Loans	518,660	337,699
Allowance for loan losses	(2,715)	(2,323)	(2,314)
Residential Portfolio Segment [Member] \| Real Estate Residential One- to Four-Family [Member]
Loans	270,583	157,505
Allowance for loan losses	(1,538)	(1,284)	(1,228)
Residential Portfolio Segment [Member] \| Multi-family Residential [Member]
Loans	39,273	20,717
Allowance for loan losses	(236)	(144)	(172)
Commercial Portfolio Segment [Member]
Loans	363,640	254,427
Allowance for loan losses	(4,453)	(3,147)	(3,039)
Consumer Portfolio Segment [Member]
Loans	79,270	50,921
Allowance for loan losses	$ (584)	$ (370)	$ (401)

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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