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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 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 + Details
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- Definition Post-modification amount of investment in financing receivables 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 + Details
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