Purchased Loans - Impaired Loans and Average Recorded Investment and Interest Income Recognized (Details) - Purchased - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Impaired loans
Unpaid Contractual Principal Balance	$ 10,911		$ 9,580
Recorded Investment With Allowance	4,310		4,869
Recorded Investment With No Allowance	5,579		3,961
Total Recorded Investment	9,889		8,830
Related Allowance	336		537
Average Recorded Investment	10,166	$ 8,737
Interest Income Recognized	57	62
Receivables Acquired with Deteriorated Credit Quality
Impaired loans
Unpaid Contractual Principal Balance	258,811		272,216
Recorded Investment With Allowance	74,499		78,611
Recorded Investment With No Allowance	134,347		143,643
Total Recorded Investment	208,846		222,254
Related Allowance	2,524		2,552
Average Recorded Investment	213,145	244,700
Interest Income Recognized	2,901	2,888
Commercial, financial, agricultural
Impaired loans
Unpaid Contractual Principal Balance	1,287		671
Recorded Investment With Allowance	914		600
Recorded Investment With No Allowance	314		11
Total Recorded Investment	1,228		611
Related Allowance	198		173
Average Recorded Investment	1,242	363
Interest Income Recognized	3	3
Commercial, financial, agricultural \| Receivables Acquired with Deteriorated Credit Quality
Impaired loans
Unpaid Contractual Principal Balance	39,542		44,403
Recorded Investment With Allowance	3,292		3,779
Recorded Investment With No Allowance	21,555		25,364
Total Recorded Investment	24,847		29,143
Related Allowance	129		161
Average Recorded Investment	27,403	16,899
Interest Income Recognized	427	225
Real estate – construction
Impaired loans
Unpaid Contractual Principal Balance	320		576
Recorded Investment With Allowance	320		576
Recorded Investment With No Allowance	0		0
Total Recorded Investment	320		576
Related Allowance	2		5
Average Recorded Investment	320	252
Interest Income Recognized	0	1
Real estate – 1-4 family mortgage
Impaired loans
Unpaid Contractual Principal Balance	6,177		5,787
Recorded Investment With Allowance	896		1,381
Recorded Investment With No Allowance	4,641		3,780
Total Recorded Investment	5,537		5,161
Related Allowance	14		18
Average Recorded Investment	5,577	6,320
Interest Income Recognized	42	40
Real estate – 1-4 family mortgage \| Receivables Acquired with Deteriorated Credit Quality
Impaired loans
Unpaid Contractual Principal Balance	52,787		53,823
Recorded Investment With Allowance	10,715		12,169
Recorded Investment With No Allowance	33,109		36,074
Total Recorded Investment	43,824		48,243
Related Allowance	420		488
Average Recorded Investment	44,177	58,749
Interest Income Recognized	572	673
Real estate – commercial mortgage
Impaired loans
Unpaid Contractual Principal Balance	2,718		2,266
Recorded Investment With Allowance	1,858		2,066
Recorded Investment With No Allowance	567		146
Total Recorded Investment	2,425		2,212
Related Allowance	119		338
Average Recorded Investment	2,630	1,642
Interest Income Recognized	12	18
Real estate – commercial mortgage \| Receivables Acquired with Deteriorated Credit Quality
Impaired loans
Unpaid Contractual Principal Balance	158,927		165,700
Recorded Investment With Allowance	59,827		62,003
Recorded Investment With No Allowance	76,455		78,435
Total Recorded Investment	136,282		140,438
Related Allowance	1,973		1,901
Average Recorded Investment	137,421	167,365
Interest Income Recognized	1,796	1,972
Installment loans to individuals
Impaired loans
Unpaid Contractual Principal Balance	409		280
Recorded Investment With Allowance	322		246
Recorded Investment With No Allowance	57		24
Total Recorded Investment	379		270
Related Allowance	3		3
Average Recorded Investment	397	160
Interest Income Recognized	0	0
Installment loans to individuals \| Receivables Acquired with Deteriorated Credit Quality
Impaired loans
Unpaid Contractual Principal Balance	7,555		8,290
Recorded Investment With Allowance	665		660
Recorded Investment With No Allowance	3,228		3,770
Total Recorded Investment	3,893		4,430
Related Allowance	2		$ 2
Average Recorded Investment	4,144	1,687
Interest Income Recognized	$ 106	$ 18

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5258-111524

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 14A
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-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953550-111524

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