Purchased Loans - Impact of Modifications Classified as Restructured Loans (Details) - Purchased loans $ in Thousands	3 Months Ended
Mar. 31, 2021 USD ($) loan	Mar. 31, 2020 USD ($) loan
Commercial, financial, agricultural
Restructured loans
Number of Loans \| loan	1
Pre- Modification Outstanding Recorded Investment	$ 135
Post- Modification Outstanding Recorded Investment	$ 135
Real estate – 1-4 family mortgage \| Primary
Restructured loans
Number of Loans \| loan		1
Pre- Modification Outstanding Recorded Investment		$ 223
Post- Modification Outstanding Recorded Investment		$ 114

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=121611835&loc=SL6953676-111524

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

+ References

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- Definition

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

+ References

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