Loans and Allowance for Loan Losses - Financial Effect of TDRs (Details) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018 USD ($) loan	Sep. 30, 2017 USD ($) loan	Sep. 30, 2018 USD ($) loan	Sep. 30, 2017 USD ($) loan
Financing Receivable Modifications [Line Items]
Number of loans \| loan	5	1	9	5
Pre-modification outstanding recorded investment	$ 198	$ 143	$ 1,340	$ 1,236
Post-modification outstanding recorded investment	$ 198	143	$ 1,340	1,236
Charge offs and specific reserves		$ 8		$ 8
Consumer and Other
Financing Receivable Modifications [Line Items]
Number of loans \| loan	4		5
Pre-modification outstanding recorded investment	$ 55		$ 61
Post-modification outstanding recorded investment	$ 55		$ 61
Commercial Real Estate \| Owner Occupied
Financing Receivable Modifications [Line Items]
Number of loans \| loan	1		1	1
Pre-modification outstanding recorded investment	$ 143		$ 143	$ 377
Post-modification outstanding recorded investment	$ 143		$ 143	$ 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
Residential Real Estate \| 1-to-4 Family Mortgage
Financing Receivable Modifications [Line Items]
Number of loans \| loan		1	1	1
Pre-modification outstanding recorded investment		$ 143	$ 249	$ 143
Post-modification outstanding recorded investment		143	$ 249	143
Charge offs and specific reserves		$ 8		$ 8
Commercial and Industrial
Financing Receivable Modifications [Line Items]
Number of loans \| loan			2	1
Pre-modification outstanding recorded investment			$ 887	$ 5
Post-modification outstanding recorded investment			$ 887	$ 5

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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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