Loans and Allowance for Loan Losses - ALL Roll Forward (Details) - USD ($)	3 Months Ended	12 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	$ 8,275,055	$ 5,860,000	$ 5,860,000
Loans charged off	(450,000)	(158,000)	(860,000)
Recoveries of loans charged off	82,000	86,000	339,000
Provision (reallocation) charged to expense	797,129	688,796	2,936,000
Ending balance	8,704,413	6,477,000	8,275,055
Commercial Real Estate [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	3,639,000	2,465,000	2,465,000
Loans charged off	0	(38,000)	(38,000)
Recoveries of loans charged off	2,000	0	2,000
Provision (reallocation) charged to expense	433,000	498,000	1,210,000
Ending balance	4,074,000	2,925,000	3,639,000
Consumer Real Estate [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	1,789,000	1,596,000	1,596,000
Loans charged off	(2,000)	0	(275,000)
Recoveries of loans charged off	4,000	23,000	100,000
Provision (reallocation) charged to expense	158,000	(100,000)	368,000
Ending balance	1,949,000	1,519,000	1,789,000
Construction and Land Development [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	795,000	521,000	521,000
Loans charged off	0	0	0
Recoveries of loans charged off	2,000	2,000	9,000
Provision (reallocation) charged to expense	57,000	104,000	265,000
Ending balance	854,000	627,000	795,000
Commercial and Industrial [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	1,746,000	1,062,000	1,062,000
Loans charged off	(318,000)	(78,000)	(177,000)
Recoveries of loans charged off	12,000	40,000	72,000
Provision (reallocation) charged to expense	269,000	186,000	789,000
Ending balance	1,709,000	1,210,000	1,746,000
Consumer and Other [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	306,000	216,000	216,000
Loans charged off	(130,000)	(42,000)	(370,000)
Recoveries of loans charged off	62,000	21,000	156,000
Provision (reallocation) charged to expense	(120,000)	1,000	304,000
Ending balance	$ 118,000	$ 196,000	$ 306,000

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.

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

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

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