Purchased Loans - Impact of Modifications Classified as Restructured Loans (Details) - Purchased loans $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2017 USD ($) loan	Sep. 30, 2016 USD ($) loan	Sep. 30, 2017 USD ($) loan	Sep. 30, 2016 USD ($) loan
Restructured loans
Number of Loans \| loan	19	2	31	8
Pre- Modification Outstanding Recorded Investment	$ 2,017	$ 132	$ 6,640	$ 495
Post- Modification Outstanding Recorded Investment	$ 1,433	$ 120	$ 5,087	$ 406
Real estate – 1-4 family mortgage
Restructured loans
Number of Loans \| loan	18	2	28	7
Pre- Modification Outstanding Recorded Investment	$ 1,624	$ 132	$ 3,789	$ 412
Post- Modification Outstanding Recorded Investment	$ 1,189	$ 120	$ 3,062	$ 325
Real estate – commercial mortgage
Restructured loans
Number of Loans \| loan	1		3	1
Pre- Modification Outstanding Recorded Investment	$ 393		$ 2,851	$ 83
Post- Modification Outstanding Recorded Investment	$ 244		$ 2,025	$ 81

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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