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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, 2017 USD ($) contract	Sep. 30, 2016 USD ($) contract	Sep. 30, 2017 USD ($) contract loan	Sep. 30, 2016 USD ($) contract loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Contracts Modified | contract	0	0		3
Pre-Modification Outstanding Recorded Investment	$ 0	$ 0		$ 1,917
Post-Modification Outstanding Recorded Investment	0	0		2,048
Post-Modification Outstanding Recorded Investment at Period End	$ 0	$ 0		$ 2,030
Number of modified TDR loans that defaulted | loan			0	0
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
Commercial real estate loans | Commercial real estate, investor
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Contracts Modified | contract				2
Pre-Modification Outstanding Recorded Investment				$ 1,830
Post-Modification Outstanding Recorded Investment				1,826
Post-Modification Outstanding Recorded Investment at Period End				$ 1,808
Residential loans | Home equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Contracts Modified | contract				1
Pre-Modification Outstanding Recorded Investment				$ 87
Post-Modification Outstanding Recorded Investment				222
Post-Modification Outstanding Recorded Investment at Period End				$ 222

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- Definition

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

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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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+ 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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+ 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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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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953682-111524

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