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
Mar. 31, 2020	Mar. 31, 2019
Noncancelable Obligations Future Minimum Payments Due [Line Items]
Allowance for loan losses, Beginning of Period	$ 8,429
Provision Allocation	(3,300)
Charge-offs	(94)	$ (578)
Recoveries	184	256
Allowance for loan losses, End of Period	11,819	8,661
Mortgage Loans on Real Estate [Member]
Noncancelable Obligations Future Minimum Payments Due [Line Items]
Allowance for loan losses, Beginning of Period	6,290
Provision Allocation	(2,477)	(902)
Charge-offs		(289)
Recoveries	144	230
Allowance for loan losses, End of Period	8,911	6,503
Commercial Loans [Member]
Noncancelable Obligations Future Minimum Payments Due [Line Items]
Allowance for loan losses, Beginning of Period	1,980
Provision Allocation	(582)	(291)
Charge-offs	(19)	(229)
Recoveries	3	2
Allowance for loan losses, End of Period	2,546	1,958
Consumer Installment Loans [Member]
Noncancelable Obligations Future Minimum Payments Due [Line Items]
Allowance for loan losses, Beginning of Period	114
Provision Allocation	(35)	(72)
Charge-offs	(75)	(60)
Recoveries	37	24
Allowance for loan losses, End of Period	111	188
All Other Loans [Member]
Noncancelable Obligations Future Minimum Payments Due [Line Items]
Allowance for loan losses, Beginning of Period	7
Provision Allocation	(1)	6
Allowance for loan losses, End of Period	8	6
Unallocated [Member]
Noncancelable Obligations Future Minimum Payments Due [Line Items]
Allowance for loan losses, Beginning of Period	38
Provision Allocation	(205)	1,259
Allowance for loan losses, End of Period	243	6
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	2,685
Provision Allocation	(234)	(855)
Recoveries	16	203
Allowance for loan losses, End of Period	2,935	3,339
Commercial [Member] \| Mortgage Loans on Real Estate [Member]
Noncancelable Obligations Future Minimum Payments Due [Line Items]
Allowance for loan losses, Beginning of Period	2,196
Provision Allocation	(2,000)	32
Charge-offs		(277)
Recoveries	44	7
Allowance for loan losses, End of Period	4,240	1,508
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	1,044
Provision Allocation	(227)	(43)
Charge-offs		(12)
Recoveries	83	18
Allowance for loan losses, End of Period	1,354	1,210
Second Mortgages [Member] \| Mortgage Loans on Real Estate [Member]
Noncancelable Obligations Future Minimum Payments Due [Line Items]
Allowance for loan losses, Beginning of Period	79
Provision Allocation	10	(40)
Recoveries	1	2
Allowance for loan losses, End of Period	70	62
Multifamily [Member] \| Mortgage Loans on Real Estate [Member]
Noncancelable Obligations Future Minimum Payments Due [Line Items]
Allowance for loan losses, Beginning of Period	248
Provision Allocation	(19)	10
Allowance for loan losses, End of Period	267	361
Agriculture [Member] \| Mortgage Loans on Real Estate [Member]
Noncancelable Obligations Future Minimum Payments Due [Line Items]
Allowance for loan losses, Beginning of Period	38
Provision Allocation	(7)	(6)
Allowance for loan losses, End of Period	$ 45	$ 23

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- Definition

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.

+ References

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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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