Purchased Loans - Deteriorated Loans (Details) - Purchased - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded Investment With Allowance	$ 4,869	$ 2,892
Recorded Investment With No Allowance	3,961	5,672
Total Recorded Investment	8,830	8,564
Unpaid Principal Balance With Allowance	5,001	2,999
Unpaid Principal Balance With no Allowance	4,579	6,204
Total Unpaid Principal Balance	9,580	9,203
With Related Allowance	537	107
With No Related Allowance	0	0
Related Allowance	537	107
Average Recorded Investment With Related Allowance	4,810	2,943
Average Recorded Investment With No Related Allowance	4,586	4,744
Average recorded investment in impaired loans	9,396	7,687	$ 6,594
Interest Income Recognized With Related Allowance	75	65
Interest Income Recognized With No Related Allowance	119	234
Interest Income, Total	194	299
Receivables Acquired with Deteriorated Credit Quality
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded Investment With Allowance	78,611	87,484
Recorded Investment With No Allowance	143,643	139,776
Total Recorded Investment	222,254	227,260
Unpaid Principal Balance With Allowance	82,605	92,483
Unpaid Principal Balance With no Allowance	189,611	185,226
Total Unpaid Principal Balance	272,216	277,709
With Related Allowance	2,552	1,777
With No Related Allowance	0	0
Related Allowance	2,552	1,777
Average Recorded Investment With Related Allowance	83,601	91,387
Average Recorded Investment With No Related Allowance	129,366	161,785
Average recorded investment in impaired loans	212,967	253,172	318,032
Interest Income Recognized With Related Allowance	4,081	4,410
Interest Income Recognized With No Related Allowance	6,003	8,459	$ 14,532
Interest Income, Total	10,084	12,869
Commercial, financial, agricultural
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded Investment With Allowance	600	625
Recorded Investment With No Allowance	11	74
Unpaid Principal Balance With Allowance	658	678
Unpaid Principal Balance With no Allowance	13	79
With Related Allowance	173	52
With No Related Allowance	0	0
Average Recorded Investment With Related Allowance	614	618
Average Recorded Investment With No Related Allowance	13	75
Interest Income Recognized With Related Allowance	10	21
Interest Income Recognized With No Related Allowance	1	3
Commercial, financial, agricultural \| Receivables Acquired with Deteriorated Credit Quality
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded Investment With Allowance	3,779	5,768
Recorded Investment With No Allowance	25,364	9,547
Unpaid Principal Balance With Allowance	4,071	6,004
Unpaid Principal Balance With no Allowance	40,332	18,175
With Related Allowance	161	312
With No Related Allowance	0	0
Average Recorded Investment With Related Allowance	4,276	5,672
Average Recorded Investment With No Related Allowance	12,102	9,208
Interest Income Recognized With Related Allowance	204	259
Interest Income Recognized With No Related Allowance	669	989
Lease financing
Accounts, Notes, Loans and Financing Receivable [Line Items]
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
Lease financing \| Receivables Acquired with Deteriorated Credit Quality
Accounts, Notes, Loans and Financing Receivable [Line Items]
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
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded Investment With Allowance	576	0
Recorded Investment With No Allowance	0	1,199
Unpaid Principal Balance With Allowance	576	0
Unpaid Principal Balance With no Allowance	0	1,207
With Related Allowance	5	0
With No Related Allowance	0	0
Average Recorded Investment With Related Allowance	576	0
Average Recorded Investment With No Related Allowance	0	318
Interest Income Recognized With Related Allowance	6	0
Interest Income Recognized With No Related Allowance	0	47
Real estate – construction \| Receivables Acquired with Deteriorated Credit Quality
Accounts, Notes, Loans and Financing Receivable [Line Items]
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 – 1-4 family mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded Investment With Allowance	1,381	1,385
Recorded Investment With No Allowance	3,780	4,225
Unpaid Principal Balance With Allowance	1,404	1,433
Unpaid Principal Balance With no Allowance	4,383	4,740
With Related Allowance	18	45
With No Related Allowance	0	0
Average Recorded Investment With Related Allowance	1,362	1,419
Average Recorded Investment With No Related Allowance	4,407	4,161
Interest Income Recognized With Related Allowance	18	18
Interest Income Recognized With No Related Allowance	111	176
Real estate – 1-4 family mortgage \| Receivables Acquired with Deteriorated Credit Quality
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded Investment With Allowance	12,169	15,910
Recorded Investment With No Allowance	36,074	38,059
Unpaid Principal Balance With Allowance	12,601	16,752
Unpaid Principal Balance With no Allowance	41,222	48,297
With Related Allowance	488	572
With No Related Allowance	0	0
Average Recorded Investment With Related Allowance	12,894	16,837
Average Recorded Investment With No Related Allowance	36,801	46,983
Interest Income Recognized With Related Allowance	647	793
Interest Income Recognized With No Related Allowance	1,647	1,993
Real estate – commercial mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded Investment With Allowance	2,066	728
Recorded Investment With No Allowance	146	165
Unpaid Principal Balance With Allowance	2,116	733
Unpaid Principal Balance With no Allowance	150	168
With Related Allowance	338	6
With No Related Allowance	0	0
Average Recorded Investment With Related Allowance	2,011	751
Average Recorded Investment With No Related Allowance	159	177
Interest Income Recognized With Related Allowance	40	26
Interest Income Recognized With No Related Allowance	7	8
Real estate – commercial mortgage \| Receivables Acquired with Deteriorated Credit Quality
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded Investment With Allowance	62,003	65,108
Recorded Investment With No Allowance	78,435	91,230
Unpaid Principal Balance With Allowance	65,273	69,029
Unpaid Principal Balance With no Allowance	100,427	117,691
With Related Allowance	1,901	892
With No Related Allowance	0	0
Average Recorded Investment With Related Allowance	65,756	68,168
Average Recorded Investment With No Related Allowance	78,368	104,485
Interest Income Recognized With Related Allowance	3,201	3,333
Interest Income Recognized With No Related Allowance	3,578	5,431
Installment loans to individuals
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded Investment With Allowance	246	154
Recorded Investment With No Allowance	24	9
Unpaid Principal Balance With Allowance	247	155
Unpaid Principal Balance With no Allowance	33	10
With Related Allowance	3	4
With No Related Allowance	0	0
Average Recorded Investment With Related Allowance	247	155
Average Recorded Investment With No Related Allowance	7	13
Interest Income Recognized With Related Allowance	1	0
Interest Income Recognized With No Related Allowance	0	0
Installment loans to individuals \| Receivables Acquired with Deteriorated Credit Quality
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded Investment With Allowance	660	698
Recorded Investment With No Allowance	3,770	940
Unpaid Principal Balance With Allowance	660	698
Unpaid Principal Balance With no Allowance	7,630	1,063
With Related Allowance	2	1
With No Related Allowance	0	0
Average Recorded Investment With Related Allowance	675	710
Average Recorded Investment With No Related Allowance	2,095	1,109
Interest Income Recognized With Related Allowance	29	25
Interest Income Recognized With No Related Allowance	$ 109	$ 46

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