Purchased Loans - Deteriorated Loans (Details) - Purchased - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Impaired loans
Recorded Investment With Allowance	$ 2,892	$ 4,538
Recorded Investment With No Allowance	5,672	1,847
Total Recorded Investment	8,564	6,385
Unpaid Principal Balance With Allowance	2,999	4,646
Unpaid Principal Balance With no Allowance	6,204	2,028
Total Unpaid Principal Balance	9,203	6,674
With Related Allowance	107	515
With No Related Allowance	0	0
Related Allowance	107	515
Average Recorded Investment With Related Allowance	2,943	4,617
Average Recorded Investment With No Related Allowance	4,744	1,977
Average recorded investment in impaired loans	7,687	6,594	$ 2,860
Interest Income Recognized With Related Allowance	65	120
Interest Income Recognized With No Related Allowance	234	48
Interest Income, Total	299	168
Commercial, financial, agricultural
Impaired loans
Recorded Investment With Allowance	625	487
Recorded Investment With No Allowance	74	224
Unpaid Principal Balance With Allowance	678	503
Unpaid Principal Balance With no Allowance	79	229
With Related Allowance	52	310
With No Related Allowance	0	0
Average Recorded Investment With Related Allowance	618	500
Average Recorded Investment With No Related Allowance	75	172
Interest Income Recognized With Related Allowance	21	2
Interest Income Recognized With No Related Allowance	3	4
Lease financing
Impaired loans
Recorded Investment With Allowance	0	0
Recorded Investment With No Allowance	0	0
Unpaid Principal Balance With Allowance	0	0
Unpaid Principal Balance With no Allowance	0	0
With Related Allowance	0	0
With No Related Allowance	0	0
Average Recorded Investment With Related Allowance	0	0
Average Recorded Investment With No Related Allowance	0	0
Interest Income Recognized With Related Allowance	0	0
Interest Income Recognized With No Related Allowance	0	0
Real estate – construction
Impaired loans
Recorded Investment With Allowance	0	145
Recorded Investment With No Allowance	1,199	0
Unpaid Principal Balance With Allowance	0	147
Unpaid Principal Balance With no Allowance	1,207	0
With Related Allowance	0	0
With No Related Allowance	0	0
Average Recorded Investment With Related Allowance	0	148
Average Recorded Investment With No Related Allowance	318	0
Interest Income Recognized With Related Allowance	0	0
Interest Income Recognized With No Related Allowance	47	0
Real estate – 1-4 family mortgage
Impaired loans
Recorded Investment With Allowance	1,385	1,496
Recorded Investment With No Allowance	4,225	1,385
Unpaid Principal Balance With Allowance	1,433	1,538
Unpaid Principal Balance With no Allowance	4,740	1,557
With Related Allowance	45	43
With No Related Allowance	0	0
Average Recorded Investment With Related Allowance	1,419	1,535
Average Recorded Investment With No Related Allowance	4,161	1,550
Interest Income Recognized With Related Allowance	18	7
Interest Income Recognized With No Related Allowance	176	33
Real estate – commercial mortgage
Impaired loans
Recorded Investment With Allowance	728	2,275
Recorded Investment With No Allowance	165	183
Unpaid Principal Balance With Allowance	733	2,299
Unpaid Principal Balance With no Allowance	168	186
With Related Allowance	6	48
With No Related Allowance	0	0
Average Recorded Investment With Related Allowance	751	2,273
Average Recorded Investment With No Related Allowance	177	194
Interest Income Recognized With Related Allowance	26	111
Interest Income Recognized With No Related Allowance	8	11
Installment loans to individuals
Impaired loans
Recorded Investment With Allowance	154	135
Recorded Investment With No Allowance	9	55
Unpaid Principal Balance With Allowance	155	159
Unpaid Principal Balance With no Allowance	10	56
With Related Allowance	4	114
With No Related Allowance	0	0
Average Recorded Investment With Related Allowance	155	161
Average Recorded Investment With No Related Allowance	13	61
Interest Income Recognized With Related Allowance	0	0
Interest Income Recognized With No Related Allowance	0	0
Receivables Acquired with Deteriorated Credit Quality
Impaired loans
Recorded Investment With Allowance	87,484	89,257
Recorded Investment With No Allowance	139,776	182,501
Total Recorded Investment	227,260	271,758
Unpaid Principal Balance With Allowance	92,483	99,504
Unpaid Principal Balance With no Allowance	185,226	240,600
Total Unpaid Principal Balance	277,709	340,104
With Related Allowance	1,777	2,820
With No Related Allowance	0	0
Related Allowance	1,777	2,820
Average Recorded Investment With Related Allowance	91,387	90,890
Average Recorded Investment With No Related Allowance	161,785	227,142
Average recorded investment in impaired loans	253,172	318,032	355,010
Interest Income Recognized With Related Allowance	4,410	3,909
Interest Income Recognized With No Related Allowance	8,459	10,623	$ 17,828
Interest Income, Total	12,869	14,532
Receivables Acquired with Deteriorated Credit Quality \| Commercial, financial, agricultural
Impaired loans
Recorded Investment With Allowance	5,768	4,555
Recorded Investment With No Allowance	9,547	7,439
Unpaid Principal Balance With Allowance	6,004	5,038
Unpaid Principal Balance With no Allowance	18,175	15,659
With Related Allowance	312	372
With No Related Allowance	0	0
Average Recorded Investment With Related Allowance	5,672	4,728
Average Recorded Investment With No Related Allowance	9,208	10,304
Interest Income Recognized With Related Allowance	259	207
Interest Income Recognized With No Related Allowance	989	819
Receivables Acquired with Deteriorated Credit Quality \| Lease financing
Impaired loans
Recorded Investment With Allowance	0	0
Recorded Investment With No Allowance	0	0
Unpaid Principal Balance With Allowance	0	0
Unpaid Principal Balance With no Allowance	0	0
With Related Allowance	0	0
With No Related Allowance	0	0
Average Recorded Investment With Related Allowance	0	0
Average Recorded Investment With No Related Allowance	0	0
Interest Income Recognized With Related Allowance	0	0
Interest Income Recognized With No Related Allowance	0	0
Receivables Acquired with Deteriorated Credit Quality \| Real estate – construction
Impaired loans
Recorded Investment With Allowance	0	0
Recorded Investment With No Allowance	0	840
Unpaid Principal Balance With Allowance	0	0
Unpaid Principal Balance With no Allowance	0	1,141
With Related Allowance	0	0
With No Related Allowance	0	0
Average Recorded Investment With Related Allowance	0	0
Average Recorded Investment With No Related Allowance	0	648
Interest Income Recognized With Related Allowance	0	0
Interest Income Recognized With No Related Allowance	0	38
Receivables Acquired with Deteriorated Credit Quality \| Real estate – 1-4 family mortgage
Impaired loans
Recorded Investment With Allowance	15,910	21,887
Recorded Investment With No Allowance	38,059	50,065
Unpaid Principal Balance With Allowance	16,752	23,128
Unpaid Principal Balance With no Allowance	48,297	63,597
With Related Allowance	572	841
With No Related Allowance	0	0
Average Recorded Investment With Related Allowance	16,837	23,021
Average Recorded Investment With No Related Allowance	46,983	64,306
Interest Income Recognized With Related Allowance	793	1,015
Interest Income Recognized With No Related Allowance	1,993	2,636
Receivables Acquired with Deteriorated Credit Quality \| Real estate – commercial mortgage
Impaired loans
Recorded Investment With Allowance	65,108	62,449
Recorded Investment With No Allowance	91,230	122,538
Unpaid Principal Balance With Allowance	69,029	70,970
Unpaid Principal Balance With no Allowance	117,691	158,105
With Related Allowance	892	1,606
With No Related Allowance	0	0
Average Recorded Investment With Related Allowance	68,168	62,759
Average Recorded Investment With No Related Allowance	104,485	149,917
Interest Income Recognized With Related Allowance	3,333	2,674
Interest Income Recognized With No Related Allowance	5,431	7,053
Receivables Acquired with Deteriorated Credit Quality \| Installment loans to individuals
Impaired loans
Recorded Investment With Allowance	698	366
Recorded Investment With No Allowance	940	1,619
Unpaid Principal Balance With Allowance	698	368
Unpaid Principal Balance With no Allowance	1,063	2,098
With Related Allowance	1	1
With No Related Allowance	0	0
Average Recorded Investment With Related Allowance	710	382
Average Recorded Investment With No Related Allowance	1,109	1,967
Interest Income Recognized With Related Allowance	25	13
Interest Income Recognized With No Related Allowance	$ 46	$ 77

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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 (c)(1)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524

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