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Loans and Allowance for Loan Losses - Troubled Debt Restructuring Modifications (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018 USD ($) contract	Sep. 30, 2017 USD ($) contract	Sep. 30, 2018 USD ($) contract loan	Sep. 30, 2017 USD ($) contract loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Contracts Modified | contract	0	0
Pre-Modification Outstanding Recorded Investment	$ 0	$ 0
Post-Modification Outstanding Recorded Investment	0	0
Post-Modification Outstanding Recorded Investment at Period End	$ 0	$ 0
Number of modified TDR loans that defaulted | loan			0	0
Commercial loans | Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Contracts Modified | contract			2
Pre-Modification Outstanding Recorded Investment			$ 254
Post-Modification Outstanding Recorded Investment			245
Post-Modification Outstanding Recorded Investment at Period End			$ 235
Consumer loans | Installment and other consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Contracts Modified | contract				1
Pre-Modification Outstanding Recorded Investment				$ 50
Post-Modification Outstanding Recorded Investment				50
Post-Modification Outstanding Recorded Investment at Period End				$ 49

X

- Definition

The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings at end of period.

+ References

No definition available.

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

+ References

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-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
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Pre-modification amount of investment in financing receivables modified by troubled debt restructurings.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
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Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default.

+ References

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-SubTopic 10
-Section 50
-Paragraph 34
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