Purchased Loans - Impact of Modifications Classified as Restructured Loans (Details) $ in Thousands	3 Months Ended
Mar. 31, 2018 USD ($) loan	Mar. 31, 2017 USD ($) loan
Real estate – commercial mortgage
Restructured loans
Number of Loans \| loan		2
Pre- Modification Outstanding Recorded Investment		$ 146
Post- Modification Outstanding Recorded Investment		$ 156
Purchased loans
Restructured loans
Number of Loans \| loan	2	14
Pre- Modification Outstanding Recorded Investment	$ 56	$ 4,942
Post- Modification Outstanding Recorded Investment	$ 51	$ 3,809
Purchased loans \| Commercial, financial, agricultural
Restructured loans
Number of Loans \| loan	1
Pre- Modification Outstanding Recorded Investment	$ 48
Post- Modification Outstanding Recorded Investment	$ 44
Purchased loans \| Real estate – 1-4 family mortgage
Restructured loans
Number of Loans \| loan		10
Pre- Modification Outstanding Recorded Investment		$ 2,221
Post- Modification Outstanding Recorded Investment		$ 1,823
Purchased loans \| 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	$ 1,986

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

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