Loans and the Allowance for Loan Losses - (Details 2) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Impaired loans
Unpaid Contractual Principal Balance	$ 40,040	$ 42,470
Recorded Investment With Allowance	34,466	36,615
Recorded Investment With No Allowance	357	12
Total Recorded Investment	34,823	36,627
Related Allowance	8,899	7,600
Receivables Acquired with Deteriorated Credit Quality
Impaired loans
Unpaid Contractual Principal Balance	371,435	430,511
Recorded Investment With Allowance	113,040	75,061
Recorded Investment With No Allowance	184,569	261,104
Total Recorded Investment	297,609	336,165
Related Allowance	3,418	1,706
Commercial, financial, agricultural
Impaired loans
Unpaid Contractual Principal Balance	2,431	1,308
Recorded Investment With Allowance	2,245	358
Recorded Investment With No Allowance	135	12
Total Recorded Investment	2,380	370
Related Allowance	1,004	6
Commercial, financial, agricultural \| Receivables Acquired with Deteriorated Credit Quality
Impaired loans
Unpaid Contractual Principal Balance	21,678	27,049
Recorded Investment With Allowance	4,729	5,197
Recorded Investment With No Allowance	7,765	11,292
Total Recorded Investment	12,494	16,489
Related Allowance	448	353
Lease financing
Impaired loans
Unpaid Contractual Principal Balance	0	0
Recorded Investment With Allowance	0	0
Recorded Investment With No Allowance	0	0
Total Recorded Investment	0	0
Related Allowance	0	0
Lease financing \| Receivables Acquired with Deteriorated Credit Quality
Impaired loans
Unpaid Contractual Principal Balance	0	0
Recorded Investment With Allowance	0	0
Recorded Investment With No Allowance	0	0
Total Recorded Investment	0	0
Related Allowance	0	0
Real estate – construction
Impaired loans
Unpaid Contractual Principal Balance	1,042	2,710
Recorded Investment With Allowance	820	2,698
Recorded Investment With No Allowance	222	0
Total Recorded Investment	1,042	2,698
Related Allowance	2	20
Real estate – construction \| Receivables Acquired with Deteriorated Credit Quality
Impaired loans
Unpaid Contractual Principal Balance	2,041	2,916
Recorded Investment With Allowance	729	0
Recorded Investment With No Allowance	993	2,749
Total Recorded Investment	1,722	2,749
Related Allowance		0
Real estate – 1-4 family mortgage
Impaired loans
Unpaid Contractual Principal Balance	20,208	18,193
Recorded Investment With Allowance	18,501	16,650
Recorded Investment With No Allowance	0	0
Total Recorded Investment	18,501	16,650
Related Allowance	5,144	4,475
Real estate – 1-4 family mortgage \| Receivables Acquired with Deteriorated Credit Quality
Impaired loans
Unpaid Contractual Principal Balance	96,394	109,293
Recorded Investment With Allowance	22,308	15,702
Recorded Investment With No Allowance	57,924	75,947
Total Recorded Investment	80,232	91,649
Related Allowance	726	256
Real estate – commercial mortgage
Impaired loans
Unpaid Contractual Principal Balance	16,126	20,169
Recorded Investment With Allowance	12,669	16,819
Recorded Investment With No Allowance	0	0
Total Recorded Investment	12,669	16,819
Related Allowance	2,635	3,099
Real estate – commercial mortgage \| Receivables Acquired with Deteriorated Credit Quality
Impaired loans
Unpaid Contractual Principal Balance	248,508	287,821
Recorded Investment With Allowance	84,859	53,762
Recorded Investment With No Allowance	116,141	168,848
Total Recorded Investment	201,000	222,610
Related Allowance	2,243	1,096
Installment loans to individuals
Impaired loans
Unpaid Contractual Principal Balance	233	90
Recorded Investment With Allowance	231	90
Recorded Investment With No Allowance	0	0
Total Recorded Investment	231	90
Related Allowance	114	0
Installment loans to individuals \| Receivables Acquired with Deteriorated Credit Quality
Impaired loans
Unpaid Contractual Principal Balance	2,814	3,432
Recorded Investment With Allowance	415	400
Recorded Investment With No Allowance	1,746	2,268
Total Recorded Investment	2,161	2,668
Related Allowance	$ 1	$ 1

Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953550-111524

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Recorded Investment
-URI http://asc.fasb.org/extlink&oid=65880944

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (a)(4)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524

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