Purchased Loans - Impact of Modifications Classified as Restructured Loans (Details) - Purchased loans $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021 USD ($) loan	Jun. 30, 2020 USD ($) loan	Jun. 30, 2021 USD ($) loan	Jun. 30, 2020 USD ($) loan
Restructured loans
Number of Loans \| loan		6	2	7
Pre- Modification Outstanding Recorded Investment		$ 1,890	$ 997	$ 2,114
Post- Modification Outstanding Recorded Investment		$ 1,893	$ 997	$ 2,008
Commercial, financial, agricultural
Restructured loans
Number of Loans \| loan		1	1	1
Pre- Modification Outstanding Recorded Investment		$ 1,029	$ 135	$ 1,029
Post- Modification Outstanding Recorded Investment		$ 1,031	$ 135	$ 1,031
Real estate – 1-4 family mortgage:
Restructured loans
Number of Loans \| loan		2		3
Pre- Modification Outstanding Recorded Investment		$ 225		$ 449
Post- Modification Outstanding Recorded Investment		$ 230		$ 345
Real estate – 1-4 family mortgage: \| Primary
Restructured loans
Number of Loans \| loan	1	1	1	2
Pre- Modification Outstanding Recorded Investment	$ 862	$ 66	$ 862	$ 290
Post- Modification Outstanding Recorded Investment	$ 862	$ 68	$ 862	$ 183
Real estate – 1-4 family mortgage: \| Home equity
Restructured loans
Number of Loans \| loan		1		1
Pre- Modification Outstanding Recorded Investment		$ 159		$ 159
Post- Modification Outstanding Recorded Investment		$ 162		$ 162
Real estate – commercial mortgage:
Restructured loans
Number of Loans \| loan		2		2
Pre- Modification Outstanding Recorded Investment		$ 611		$ 611
Post- Modification Outstanding Recorded Investment		$ 613		$ 613
Real estate – commercial mortgage: \| Owner-occupied
Restructured loans
Number of Loans \| loan		1		1
Pre- Modification Outstanding Recorded Investment		$ 69		$ 69
Post- Modification Outstanding Recorded Investment		$ 69		$ 69
Real estate – commercial mortgage: \| Non-owner occupied
Restructured loans
Number of Loans \| loan		1		1
Pre- Modification Outstanding Recorded Investment		$ 542		$ 542
Post- Modification Outstanding Recorded Investment		$ 544		$ 544
Installment loans to individuals
Restructured loans
Number of Loans \| loan		1		1
Pre- Modification Outstanding Recorded Investment		$ 25		$ 25
Post- Modification Outstanding Recorded Investment		$ 19		$ 19

Troubled Debt Restructuring Financing Receivable Modifications [Abstract]

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953676-111524

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Amount, after troubled debt restructuring, of modified financing receivable.

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- Definition

Amount, before troubled debt restructuring, of financing receivable to be modified.

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