Purchased Loans - Impaired Loans and Average Recorded Investment and Interest Income Recognized (Details) - Purchased - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Impaired loans
Unpaid Contractual Principal Balance	$ 9,885		$ 9,885		$ 9,580
Recorded Investment With Allowance	5,312		5,312		4,869
Recorded Investment With No Allowance	3,823		3,823		3,961
Total Recorded Investment	9,135		9,135		8,830
Related Allowance	252		252		537
Average Recorded Investment	9,133	$ 7,224	9,128	$ 7,361
Interest Income Recognized	50	49	98	110
Receivables Acquired with Deteriorated Credit Quality
Impaired loans
Unpaid Contractual Principal Balance	238,868		238,868		272,216
Recorded Investment With Allowance	73,982		73,982		78,611
Recorded Investment With No Allowance	117,363		117,363		143,643
Total Recorded Investment	191,345		191,345		222,254
Related Allowance	2,666		2,666		2,552
Average Recorded Investment	193,002	231,812	196,333	233,943
Interest Income Recognized	2,728	2,790	5,699	5,678
Commercial, financial, agricultural
Impaired loans
Unpaid Contractual Principal Balance	1,038		1,038		671
Recorded Investment With Allowance	687		687		600
Recorded Investment With No Allowance	335		335		11
Total Recorded Investment	1,022		1,022		611
Related Allowance	63		63		173
Average Recorded Investment	1,010	380	941	383
Interest Income Recognized	2	3	4	6
Commercial, financial, agricultural \| Receivables Acquired with Deteriorated Credit Quality
Impaired loans
Unpaid Contractual Principal Balance	38,140		38,140		44,403
Recorded Investment With Allowance	4,064		4,064		3,779
Recorded Investment With No Allowance	19,562		19,562		25,364
Total Recorded Investment	23,626		23,626		29,143
Related Allowance	171		171		161
Average Recorded Investment	23,976	12,815	25,667	13,051
Interest Income Recognized	388	192	863	417
Lease financing
Impaired loans
Average Recorded Investment			0	0
Interest Income Recognized			0	0
Lease financing \| Receivables Acquired with Deteriorated Credit Quality
Impaired loans
Average Recorded Investment			0	0
Interest Income Recognized			0	0
Real estate – construction
Impaired loans
Unpaid Contractual Principal Balance	256		256		576
Recorded Investment With Allowance	256		256		576
Recorded Investment With No Allowance	0		0		0
Total Recorded Investment	256		256		576
Related Allowance	2		2		5
Average Recorded Investment	256	0	256	0
Interest Income Recognized	0	0	3	0
Real estate – construction \| Receivables Acquired with Deteriorated Credit Quality
Impaired loans
Average Recorded Investment			0	0
Interest Income Recognized			0	0
Real estate – 1-4 family mortgage
Impaired loans
Unpaid Contractual Principal Balance	6,095		6,095		5,787
Recorded Investment With Allowance	2,194		2,194		1,381
Recorded Investment With No Allowance	3,234		3,234		3,780
Total Recorded Investment	5,428		5,428		5,161
Related Allowance	21		21		18
Average Recorded Investment	5,415	5,135	5,450	5,252
Interest Income Recognized	36	34	66	74
Real estate – 1-4 family mortgage \| Receivables Acquired with Deteriorated Credit Quality
Impaired loans
Unpaid Contractual Principal Balance	51,209		51,209		53,823
Recorded Investment With Allowance	10,753		10,753		12,169
Recorded Investment With No Allowance	31,926		31,926		36,074
Total Recorded Investment	42,679		42,679		48,243
Related Allowance	515		515		488
Average Recorded Investment	43,011	54,634	43,360	55,293
Interest Income Recognized	571	647	1,161	1,320
Real estate – commercial mortgage
Impaired loans
Unpaid Contractual Principal Balance	2,110		2,110		2,266
Recorded Investment With Allowance	1,851		1,851		2,066
Recorded Investment With No Allowance	213		213		146
Total Recorded Investment	2,064		2,064		2,212
Related Allowance	163		163		338
Average Recorded Investment	2,082	1,462	2,109	1,479
Interest Income Recognized	12	12	25	30
Real estate – commercial mortgage \| Receivables Acquired with Deteriorated Credit Quality
Impaired loans
Unpaid Contractual Principal Balance	142,859		142,859		165,700
Recorded Investment With Allowance	58,507		58,507		62,003
Recorded Investment With No Allowance	63,191		63,191		78,435
Total Recorded Investment	121,698		121,698		140,438
Related Allowance	1,978		1,978		1,901
Average Recorded Investment	122,455	162,712	123,526	163,959
Interest Income Recognized	1,674	1,933	3,474	3,905
Installment loans to individuals
Impaired loans
Unpaid Contractual Principal Balance	386		386		280
Recorded Investment With Allowance	324		324		246
Recorded Investment With No Allowance	41		41		24
Total Recorded Investment	365		365		270
Related Allowance	3		3		3
Average Recorded Investment	370	247	372	247
Interest Income Recognized	0	0	0	0
Installment loans to individuals \| Receivables Acquired with Deteriorated Credit Quality
Impaired loans
Unpaid Contractual Principal Balance	6,660		6,660		8,290
Recorded Investment With Allowance	658		658		660
Recorded Investment With No Allowance	2,684		2,684		3,770
Total Recorded Investment	3,342		3,342		4,430
Related Allowance	2		2		$ 2
Average Recorded Investment	3,560	1,651	3,780	1,640
Interest Income Recognized	$ 95	$ 18	$ 201	$ 36

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=118936363&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=118936363&loc=d3e5258-111524

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