Purchased Loans - Deteriorated Loans (Details) - Purchased - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded Investment With Allowance	$ 8,228	$ 4,869
Recorded Investment With No Allowance	5,644	3,961
Total Recorded Investment	13,872	8,830
Unpaid Principal Balance With Allowance	8,605	5,001
Unpaid Principal Balance With No Allowance	6,457	4,579
Total Unpaid Principal Balance	15,062	9,580
With Related Allowance	253	537
With No Related Allowance	0	0
Related Allowance	253	537
Average Recorded Investment With Related Allowance	8,113	4,810
Average Recorded Investment With No Related Allowance	6,038	4,586
Average recorded investment in impaired loans	14,151	9,396	$ 7,687
Interest Income Recognized With Related Allowance	92	75
Interest Income Recognized With No Related Allowance	80	119
Interest Income, Total	172	194
Receivables Acquired with Deteriorated Credit Quality
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded Investment With Allowance	66,897	78,611
Recorded Investment With No Allowance	105,367	143,643
Total Recorded Investment	172,264	222,254
Unpaid Principal Balance With Allowance	73,399	82,605
Unpaid Principal Balance With No Allowance	144,954	189,611
Total Unpaid Principal Balance	218,353	272,216
With Related Allowance	1,971	2,552
With No Related Allowance	0	0
Related Allowance	1,971	2,552
Average Recorded Investment With Related Allowance	72,825	83,601
Average Recorded Investment With No Related Allowance	121,658	129,366
Average recorded investment in impaired loans	194,483	212,967	253,172
Interest Income Recognized With Related Allowance	3,649	4,081
Interest Income Recognized With No Related Allowance	6,729	6,003	$ 12,869
Interest Income, Total	10,378	10,084
Commercial, financial, agricultural
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded Investment With Allowance	1,837	600
Recorded Investment With No Allowance	901	11
Unpaid Principal Balance With Allowance	2,074	658
Unpaid Principal Balance With No Allowance	905	13
With Related Allowance	212	173
With No Related Allowance	0	0
Average Recorded Investment With Related Allowance	1,700	614
Average Recorded Investment With No Related Allowance	912	13
Interest Income Recognized With Related Allowance	8	10
Interest Income Recognized With No Related Allowance	0	1
Commercial, financial, agricultural \| Receivables Acquired with Deteriorated Credit Quality
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded Investment With Allowance	3,695	3,779
Recorded Investment With No Allowance	25,843	25,364
Unpaid Principal Balance With Allowance	7,370	4,071
Unpaid Principal Balance With No Allowance	41,792	40,332
With Related Allowance	292	161
With No Related Allowance	0	0
Average Recorded Investment With Related Allowance	6,919	4,276
Average Recorded Investment With No Related Allowance	37,535	12,102
Interest Income Recognized With Related Allowance	187	204
Interest Income Recognized With No Related Allowance	1,208	669
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	2,499	576
Recorded Investment With No Allowance	772	0
Unpaid Principal Balance With Allowance	2,490	576
Unpaid Principal Balance With No Allowance	779	0
With Related Allowance	16	5
With No Related Allowance	0	0
Average Recorded Investment With Related Allowance	2,386	576
Average Recorded Investment With No Related Allowance	770	0
Interest Income Recognized With Related Allowance	3	6
Interest Income Recognized With No Related Allowance	0	0
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	863	0
Unpaid Principal Balance With Allowance	0	0
Unpaid Principal Balance With No Allowance	882	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	618	0
Interest Income Recognized With Related Allowance	0	0
Interest Income Recognized With No Related Allowance	21	0
Real estate – 1-4 family mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded Investment With Allowance	2,801	1,381
Recorded Investment With No Allowance	3,772	3,780
Unpaid Principal Balance With Allowance	2,914	1,404
Unpaid Principal Balance With No Allowance	4,550	4,383
With Related Allowance	17	18
With No Related Allowance	0	0
Average Recorded Investment With Related Allowance	2,900	1,362
Average Recorded Investment With No Related Allowance	4,134	4,407
Interest Income Recognized With Related Allowance	41	18
Interest Income Recognized With No Related Allowance	73	111
Real estate – 1-4 family mortgage \| Receivables Acquired with Deteriorated Credit Quality
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded Investment With Allowance	10,061	12,169
Recorded Investment With No Allowance	25,482	36,074
Unpaid Principal Balance With Allowance	10,372	12,601
Unpaid Principal Balance With No Allowance	32,597	41,222
With Related Allowance	291	488
With No Related Allowance	0	0
Average Recorded Investment With Related Allowance	10,369	12,894
Average Recorded Investment With No Related Allowance	26,687	36,801
Interest Income Recognized With Related Allowance	529	647
Interest Income Recognized With No Related Allowance	1,665	1,647
Real estate – commercial mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded Investment With Allowance	981	2,066
Recorded Investment With No Allowance	128	146
Unpaid Principal Balance With Allowance	1,017	2,116
Unpaid Principal Balance With No Allowance	131	150
With Related Allowance	6	338
With No Related Allowance	0	0
Average Recorded Investment With Related Allowance	1,031	2,011
Average Recorded Investment With No Related Allowance	137	159
Interest Income Recognized With Related Allowance	40	40
Interest Income Recognized With No Related Allowance	7	7
Real estate – commercial mortgage \| Receivables Acquired with Deteriorated Credit Quality
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded Investment With Allowance	52,501	62,003
Recorded Investment With No Allowance	50,632	78,435
Unpaid Principal Balance With Allowance	55,017	65,273
Unpaid Principal Balance With No Allowance	64,912	100,427
With Related Allowance	1,386	1,901
With No Related Allowance	0	0
Average Recorded Investment With Related Allowance	54,885	65,756
Average Recorded Investment With No Related Allowance	53,586	78,368
Interest Income Recognized With Related Allowance	2,904	3,201
Interest Income Recognized With No Related Allowance	3,500	3,578
Installment loans to individuals
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded Investment With Allowance	110	246
Recorded Investment With No Allowance	71	24
Unpaid Principal Balance With Allowance	110	247
Unpaid Principal Balance With No Allowance	92	33
With Related Allowance	2	3
With No Related Allowance	0	0
Average Recorded Investment With Related Allowance	96	247
Average Recorded Investment With No Related Allowance	85	7
Interest Income Recognized With Related Allowance	0	1
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	640	660
Recorded Investment With No Allowance	2,547	3,770
Unpaid Principal Balance With Allowance	640	660
Unpaid Principal Balance With No Allowance	4,771	7,630
With Related Allowance	2	2
With No Related Allowance	0	0
Average Recorded Investment With Related Allowance	652	675
Average Recorded Investment With No Related Allowance	3,232	2,095
Interest Income Recognized With Related Allowance	29	29
Interest Income Recognized With No Related Allowance	$ 335	$ 109

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