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Allowance for Loan Losses - Recorded Investment in Consumer Loan Classes by Performing and Nonperforming Status (Details) - Consumer - USD ($) $ in Thousands | Sep. 30, 2017 | Dec. 31, 2016
--- | --- | ---
Financing Receivable, Recorded Investment [Line Items] |  |
Loans and leases receivables, recorded investment | $ 1,259,367 | $ 1,256,024
Percentage of Total | 100.00% | 100.00%
Performing |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans and leases receivables, recorded investment | $ 1,247,862 | $ 1,242,559
Percentage of Total | 99.10% | 98.90%
Nonperforming |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans and leases receivables, recorded investment | $ 11,505 | $ 13,465
Percentage of Total | 0.90% | 1.10%
Residential Mortgage |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans and leases receivables, recorded investment | $ 697,367 | $ 701,982
Percentage of Total | 100.00% | 100.00%
Residential Mortgage | Performing |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans and leases receivables, recorded investment | $ 689,585 | $ 692,064
Percentage of Total | 98.90% | 98.60%
Residential Mortgage | Nonperforming |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans and leases receivables, recorded investment | $ 7,782 | $ 9,918
Percentage of Total | 1.10% | 1.40%
Home Equity |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans and leases receivables, recorded investment | $ 487,806 | $ 482,284
Percentage of Total | 100.00% | 100.00%
Home Equity | Performing |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans and leases receivables, recorded investment | $ 484,131 | $ 478,845
Percentage of Total | 99.20% | 99.30%
Home Equity | Nonperforming |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans and leases receivables, recorded investment | $ 3,675 | $ 3,439
Percentage of Total | 0.80% | 0.70%
Installment and Other Consumer |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans and leases receivables, recorded investment | $ 69,644 | $ 65,852
Percentage of Total | 100.00% | 100.00%
Installment and Other Consumer | Performing |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans and leases receivables, recorded investment | $ 69,596 | $ 65,744
Percentage of Total | 99.90% | 99.80%
Installment and Other Consumer | Nonperforming |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans and leases receivables, recorded investment | $ 48 | $ 108
Percentage of Total | 0.10% | 0.20%
Consumer Construction |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans and leases receivables, recorded investment | $ 4,550 | $ 5,906
Percentage of Total | 100.00% | 100.00%
Consumer Construction | Performing |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans and leases receivables, recorded investment | $ 4,550 | $ 5,906
Percentage of Total | 100.00% | 100.00%
Consumer Construction | Nonperforming |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Loans and leases receivables, recorded investment | $ 0 | $ 0
Percentage of Total | 0.00% | 0.00%

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- Definition Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522 + Details
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