Purchased Loans - Impact of Modifications Classified as Restructured Loans (Details) - Purchased loans $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019 USD ($) loan	Sep. 30, 2019 USD ($) loan	Sep. 30, 2018 USD ($) loan
Restructured loans
Number of Loans \| loan	2	4	3
Pre- Modification Outstanding Recorded Investment	$ 292	$ 2,892	$ 74
Post- Modification Outstanding Recorded Investment	$ 292	$ 2,888	$ 68
Commercial, financial, agricultural
Restructured loans
Number of Loans \| loan	1	2	1
Pre- Modification Outstanding Recorded Investment	$ 258	$ 2,778	$ 48
Post- Modification Outstanding Recorded Investment	$ 258	$ 2,778	$ 44
Real estate – 1-4 family mortgage
Restructured loans
Number of Loans \| loan	1	1	1
Pre- Modification Outstanding Recorded Investment	$ 34	$ 34	$ 18
Post- Modification Outstanding Recorded Investment	$ 34	$ 34	$ 17
Real estate – commercial mortgage
Restructured loans
Number of Loans \| loan		1	1
Pre- Modification Outstanding Recorded Investment		$ 80	$ 8
Post- Modification Outstanding Recorded Investment		$ 76	$ 7

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=118936363&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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