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	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Noncancelable Obligations Future Minimum Payments Due [Line Items]
Allowance for loan losses, Beginning of Period	$ 11,819	$ 8,661	$ 8,429	$ 8,983
Provision Allocation	900	125	4,200	125
Charge-offs	(618)	(102)	(712)	(680)
Recoveries	137	135	321	391
Allowance for loan losses, End of Period	12,238	8,819	12,238	8,819
Mortgage Loans on Real Estate [Member]
Noncancelable Obligations Future Minimum Payments Due [Line Items]
Allowance for loan losses, Beginning of Period	8,911	6,503	6,290	5,660
Provision Allocation	1,076	15	3,553	917
Charge-offs		(34)		(323)
Recoveries	50	108	194	338
Allowance for loan losses, End of Period	10,037	6,592	10,037	6,592
Commercial Loans [Member]
Noncancelable Obligations Future Minimum Payments Due [Line Items]
Allowance for loan losses, Beginning of Period	2,546	1,958	1,980	1,894
Provision Allocation	37	86	619	377
Charge-offs	(589)	(28)	(608)	(257)
Recoveries	64	2	67	4
Allowance for loan losses, End of Period	2,058	2,018	2,058	2,018
Consumer Installment Loans [Member]
Noncancelable Obligations Future Minimum Payments Due [Line Items]
Allowance for loan losses, Beginning of Period	111	188	114	152
Provision Allocation	5	12	40	84
Charge-offs	(29)	(40)	(104)	(100)
Recoveries	23	25	60	49
Allowance for loan losses, End of Period	110	185	110	185
All Other Loans [Member]
Noncancelable Obligations Future Minimum Payments Due [Line Items]
Allowance for loan losses, Beginning of Period	8	6	7	12
Provision Allocation		15	1	9
Allowance for loan losses, End of Period	8	21	8	21
Unallocated [Member]
Noncancelable Obligations Future Minimum Payments Due [Line Items]
Allowance for loan losses, Beginning of Period	243	6	38	1,265
Provision Allocation	(218)	(3)	(13)	(1,262)
Allowance for loan losses, End of Period	25	3	25	3
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	2,935	3,339	2,685	2,281
Provision Allocation	547	(426)	781	429
Charge-offs		(34)		(34)
Recoveries	13	15	29	218
Allowance for loan losses, End of Period	3,495	2,894	3,495	2,894
Commercial [Member] \| Mortgage Loans on Real Estate [Member]
Noncancelable Obligations Future Minimum Payments Due [Line Items]
Allowance for loan losses, Beginning of Period	4,240	1,508	2,196	1,810
Provision Allocation	337	461	2,337	429
Charge-offs				(277)
Recoveries	35	57	79	64
Allowance for loan losses, End of Period	4,612	2,026	4,612	2,026
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	1,354	1,210	1,044	1,161
Provision Allocation	(13)	154	214	197
Charge-offs				(12)
Recoveries	1	35	84	53
Allowance for loan losses, End of Period	1,342	1,399	1,342	1,399
Second Mortgages [Member] \| Mortgage Loans on Real Estate [Member]
Noncancelable Obligations Future Minimum Payments Due [Line Items]
Allowance for loan losses, Beginning of Period	70	62	79	20
Provision Allocation	(26)	18	(36)	58
Recoveries	1	1	2	3
Allowance for loan losses, End of Period	45	81	45	81
Multifamily [Member] \| Mortgage Loans on Real Estate [Member]
Noncancelable Obligations Future Minimum Payments Due [Line Items]
Allowance for loan losses, Beginning of Period	267	361	248	371
Provision Allocation	232	(169)	251	(179)
Allowance for loan losses, End of Period	499	192	499	192
Agriculture [Member] \| Mortgage Loans on Real Estate [Member]
Noncancelable Obligations Future Minimum Payments Due [Line Items]
Allowance for loan losses, Beginning of Period	45	23	38	17
Provision Allocation	(1)	$ (23)	6	$ (17)
Allowance for loan losses, End of Period	$ 44		$ 44

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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