Loans - Allowance for Credit Losses on Financing Receivables (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Allowance for Loan Losses:
Beginning Balance	$ 12,896	$ 12,044
Charge-offs	(388)	(51)
Recoveries	67	39
Provision for loan losses	330	350
Provision	12,905	12,382
Commercial, financial, and agricultural
Allowance for Loan Losses:
Beginning Balance	1,554	1,532
Charge-offs	(213)	0
Recoveries	6	0
Provision for loan losses	94	(278)
Provision	1,441	1,254
Real estate mortgage \| Residential
Allowance for Loan Losses:
Beginning Balance	5,383	5,116
Charge-offs	(98)	0
Recoveries	30	3
Provision for loan losses	256	4
Provision	5,571	5,123
Real estate mortgage \| Commercial
Allowance for Loan Losses:
Beginning Balance	4,975	4,217
Charge-offs	0	0
Recoveries	0	5
Provision for loan losses	(509)	250
Provision	4,466	4,472
Real estate mortgage \| Construction
Allowance for Loan Losses:
Beginning Balance	178	160
Charge-offs	0	0
Recoveries	3	3
Provision for loan losses	6	(16)
Provision	187	147
Installment loans to individuals
Allowance for Loan Losses:
Beginning Balance	416	243
Charge-offs	(77)	(51)
Recoveries	28	28
Provision for loan losses	181	44
Provision	548	264
Unallocated Financing Receivables [Member]
Allowance for Loan Losses:
Beginning Balance	390	776
Charge-offs	0	0
Recoveries	0	0
Provision for loan losses	302	346
Provision	$ 692	$ 1,122

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953423-111524

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7(d))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 6
-Section L
-Subsection 1

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
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-Subparagraph (SX 210.9-04.11)
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