Loans and Allowance for Loan Losses - Financial Effect of TDRs (Details) $ in Thousands	3 Months Ended
Mar. 31, 2018 USD ($) loan	Mar. 31, 2017 USD ($) loan
Financing Receivable Modifications [Line Items]
Number of loans \| loan	2	4
Pre-modification outstanding recorded investment	$ 254	$ 1,093
Post-modification outstanding recorded investment	$ 254	$ 1,093
Residential Real Estate \| 1-to-4 Family Mortgage
Financing Receivable Modifications [Line Items]
Number of loans \| loan	1	1
Pre-modification outstanding recorded investment	$ 249	$ 5
Post-modification outstanding recorded investment	$ 249	$ 5
Consumer and Other
Financing Receivable Modifications [Line Items]
Number of loans \| loan	1
Pre-modification outstanding recorded investment	$ 5
Post-modification outstanding recorded investment	$ 5
Commercial Real Estate \| Owner Occupied
Financing Receivable Modifications [Line Items]
Number of loans \| loan		1
Pre-modification outstanding recorded investment		$ 377
Post-modification outstanding recorded investment		$ 377
Commercial Real Estate \| Non-Owner Occupied
Financing Receivable Modifications [Line Items]
Number of loans \| loan		2
Pre-modification outstanding recorded investment		$ 711
Post-modification outstanding recorded investment		$ 711

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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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