Loans and Related Allowance for Loan Losses (Allowance for Loan Losses on Loans, Excluding PCI Loans, by Segment) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Noncancelable Obligations Future Minimum Payments Due [Line Items]
Allowance for loan losses, Beginning of Period	$ 12,238	$ 8,819	$ 8,429	$ 8,983
Provision Allocation			4,200	125
Charge-offs	(42)	(576)	(754)	(1,256)
Recoveries	132	150	453	541
Allowance for loan losses, End of Period	12,328	8,393	12,328	8,393
Mortgage Loans on Real Estate [Member]
Noncancelable Obligations Future Minimum Payments Due [Line Items]
Allowance for loan losses, Beginning of Period	10,037	6,624	6,290	5,660
Provision Allocation	(2,788)	(596)	765	353
Charge-offs		(344)		(667)
Recoveries	96	94	290	432
Allowance for loan losses, End of Period	7,345	5,778	7,345	5,778
Commercial Loans [Member]
Noncancelable Obligations Future Minimum Payments Due [Line Items]
Allowance for loan losses, Beginning of Period	2,058	1,999	1,980	1,894
Provision Allocation	(288)	(229)	331	129
Charge-offs		(98)	(608)	(355)
Recoveries	19	3	86	7
Allowance for loan losses, End of Period	1,789	1,675	1,789	1,675
Consumer Installment Loans [Member]
Noncancelable Obligations Future Minimum Payments Due [Line Items]
Allowance for loan losses, Beginning of Period	110	185	114	152
Provision Allocation	31	32	71	116
Charge-offs	(42)	(134)	(146)	(234)
Recoveries	17	53	77	102
Allowance for loan losses, End of Period	116	136	116	136
All Other Loans [Member]
Noncancelable Obligations Future Minimum Payments Due [Line Items]
Allowance for loan losses, Beginning of Period	8	8	7	12
Provision Allocation	2		3	(4)
Allowance for loan losses, End of Period	10	8	10	8
Unallocated [Member]
Noncancelable Obligations Future Minimum Payments Due [Line Items]
Allowance for loan losses, Beginning of Period	25	3	38	1,265
Provision Allocation	3,043	793	3,030	(469)
Allowance for loan losses, End of Period	3,068	796	3,068	796
Residential 1-4 Family [Member] \| Mortgage Loans on Real Estate [Member]
Noncancelable Obligations Future Minimum Payments Due [Line Items]
Allowance for loan losses, Beginning of Period	3,495	2,894	2,685	2,281
Provision Allocation	(954)	(35)	(173)	394
Charge-offs		(144)		(178)
Recoveries	14	26	43	244
Allowance for loan losses, End of Period	2,555	2,741	2,555	2,741
Commercial [Member] \| Mortgage Loans on Real Estate [Member]
Noncancelable Obligations Future Minimum Payments Due [Line Items]
Allowance for loan losses, Beginning of Period	4,612	2,026	2,196	1,810
Provision Allocation	(1,606)	1	731	430
Charge-offs				(277)
Recoveries	5	7	84	71
Allowance for loan losses, End of Period	3,011	2,034	3,011	2,034
Construction and Land Development [Member] \| Mortgage Loans on Real Estate [Member]
Noncancelable Obligations Future Minimum Payments Due [Line Items]
Allowance for loan losses, Beginning of Period	1,342	1,399	1,044	1,161
Provision Allocation	(254)	(587)	(40)	(390)
Charge-offs		(200)		(212)
Recoveries	75	18	159	71
Allowance for loan losses, End of Period	1,163	630	1,163	630
Second Mortgages [Member] \| Mortgage Loans on Real Estate [Member]
Noncancelable Obligations Future Minimum Payments Due [Line Items]
Allowance for loan losses, Beginning of Period	45	81	79	20
Provision Allocation	(9)	(7)	(45)	51
Recoveries	2	2	4	5
Allowance for loan losses, End of Period	38	76	38	76
Multifamily [Member] \| Mortgage Loans on Real Estate [Member]
Noncancelable Obligations Future Minimum Payments Due [Line Items]
Allowance for loan losses, Beginning of Period	499	192	248	371
Provision Allocation	28	17	279	(162)
Recoveries		41		41
Allowance for loan losses, End of Period	527	250	527	250
Agriculture [Member] \| Mortgage Loans on Real Estate [Member]
Noncancelable Obligations Future Minimum Payments Due [Line Items]
Allowance for loan losses, Beginning of Period	44	32	38	17
Provision Allocation	7	15	13	30
Allowance for loan losses, End of Period	$ 51	$ 47	$ 51	$ 47

Noncancelable obligations future minimum payments due.

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

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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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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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