Loans and Allowance for Loan Losses - ALL Roll Forward (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	$ 8,704	$ 6,477	$ 8,275	$ 5,860
Loans charged off	(94)	(84)	(545)	(242)
Recoveries of charge-offs	94	64	177	151
Provision (reallocation) charged to expense	393	617	1,190	1,305
Ending balance	9,097	7,074	9,097	7,074
Commercial Real Estate [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	4,074	2,925	3,639	2,465
Loans charged off	0	0	0	(38)
Recoveries of charge-offs	22	0	24	0
Provision (reallocation) charged to expense	6	210	439	708
Ending balance	4,102	3,135	4,102	3,135
Consumer Real Estate [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	1,949	1,519	1,789	1,596
Loans charged off	0	(25)	(2)	(25)
Recoveries of charge-offs	16	27	20	50
Provision (reallocation) charged to expense	224	7	382	(93)
Ending balance	2,189	1,528	2,189	1,528
Construction and Land Development [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	854	627	795	521
Loans charged off	0	0	0	0
Recoveries of charge-offs	2	3	4	5
Provision (reallocation) charged to expense	90	114	147	218
Ending balance	946	744	946	744
Commercial and Industrial [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	1,709	1,210	1,746	1,062
Loans charged off	(14)	0	(333)	(78)
Recoveries of charge-offs	41	16	53	56
Provision (reallocation) charged to expense	10	141	280	327
Ending balance	1,746	1,367	1,746	1,367
Consumer and Other [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	118	196	306	216
Loans charged off	(80)	(59)	(210)	(101)
Recoveries of charge-offs	13	18	76	40
Provision (reallocation) charged to expense	63	145	(58)	145
Ending balance	$ 114	$ 300	$ 114	$ 300

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

+ References

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- Definition

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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- Definition

Amount of expense related to estimated loss from loan and lease transactions.

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