Purchased Loans - Impact of Modifications Classified as Restructured Loans (Details) - Purchased loans $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018 loan	Sep. 30, 2017 USD ($) loan	Sep. 30, 2018 USD ($) loan	Sep. 30, 2017 USD ($) loan
Restructured loans
Number of Loans \| loan	0	19	3	31
Pre- Modification Outstanding Recorded Investment		$ 2,017	$ 74	$ 6,640
Post- Modification Outstanding Recorded Investment		$ 1,433	$ 68	$ 5,087
Commercial, financial, agricultural
Restructured loans
Number of Loans \| loan			1
Pre- Modification Outstanding Recorded Investment			$ 48
Post- Modification Outstanding Recorded Investment			$ 44
Real estate – 1-4 family mortgage
Restructured loans
Number of Loans \| loan		18	1	28
Pre- Modification Outstanding Recorded Investment		$ 1,624	$ 18	$ 3,789
Post- Modification Outstanding Recorded Investment		$ 1,189	$ 17	$ 3,062
Real estate – commercial mortgage
Restructured loans
Number of Loans \| loan		1	1	3
Pre- Modification Outstanding Recorded Investment		$ 393	$ 8	$ 2,851
Post- Modification Outstanding Recorded Investment		$ 244	$ 7	$ 2,025

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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524

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Post-modification amount of investment in financing receivables modified by troubled debt restructurings.

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