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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Loans and Allowance for Loan Losses, Summary of Loans (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017
Summary of loans [Abstract]
Gross loans	$ 632,958		$ 601,902
Less allowance for loan losses	(7,836)	$ (7,835)	(7,832)	$ (7,702)	$ (7,699)	$ (7,654)
Less deferred loan fees	(1,508)		(1,992)
Net loans	623,614		592,078
Construction & Development [Member]
Summary of loans [Abstract]
Gross loans	83,291		87,267
Less allowance for loan losses	(1,031)	(1,290)	(1,136)	(1,283)	(1,465)	(1,407)
1-4 Family Commercial [Member]
Summary of loans [Abstract]
Gross loans	36,165		33,278
Less allowance for loan losses	(448)	(452)	(433)	(435)	(497)	(431)
Commercial Real Estate - Other [Member]
Summary of loans [Abstract]
Gross loans	188,142		156,396
Less allowance for loan losses	(2,329)	(2,087)	(2,035)	(1,972)	(1,556)	(1,865)
Commercial Real Estate [Member]
Summary of loans [Abstract]
Gross loans	307,598		276,941
Commercial & Industrial [Member]
Summary of loans [Abstract]
Gross loans	256,100		248,394
Less allowance for loan losses	(3,171)	(3,068)	(3,231)	(3,013)	(3,108)	(2,779)
Agricultural [Member]
Summary of loans [Abstract]
Gross loans	56,167		62,844
Less allowance for loan losses	(695)	(760)	(818)	(808)	(872)	(1,015)
Consumer [Member]
Summary of loans [Abstract]
Gross loans	13,093		13,723
Less allowance for loan losses	$ (162)	$ (178)	$ (179)	$ (191)	$ (201)	$ (157)