Purchased Loans - Impact of Modifications Classified as Restructured Loans (Details) - Purchased loans $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018 USD ($) loan	Jun. 30, 2017 USD ($) loan	Jun. 30, 2018 USD ($) loan	Jun. 30, 2017 USD ($) loan
Restructured loans
Number of Loans \| loan	1	4	3	18
Pre- Modification Outstanding Recorded Investment	$ 18	$ 463	$ 74	$ 5,405
Post- Modification Outstanding Recorded Investment	$ 17	$ 367	$ 68	$ 4,177
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	1	4	1	14
Pre- Modification Outstanding Recorded Investment	$ 18	$ 463	$ 18	$ 2,684
Post- Modification Outstanding Recorded Investment	$ 17	$ 367	$ 17	$ 2,178
Real estate – commercial mortgage
Restructured loans
Number of Loans \| loan			1	4
Pre- Modification Outstanding Recorded Investment			$ 8	$ 2,721
Post- Modification Outstanding Recorded Investment			$ 7	$ 1,999

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/2003/role/presentationRef
-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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