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Fair Value Measurement - Summary of Assets Measured at Fair Value on Non-recurring Basis, Excluding Acquired Impaired Loans (Details) - USD ($) $ in Thousands | Dec. 31, 2017 | Dec. 31, 2016
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Commercial Real Estate |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |
Assets, Fair Value | $ 12,783 | $ 8,916
Residential Real Estate |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |
Assets, Fair Value | 2,271 | 1,007
Commercial and Industrial |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |
Assets, Fair Value | 12,092 | 986
Other Real Estate Owned |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |
Assets, Fair Value | 10,626 | 16,570
Level 3 | Commercial Real Estate |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |
Assets, Fair Value | 12,783 | 8,916
Level 3 | Residential Real Estate |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |
Assets, Fair Value | 2,271 | 1,007
Level 3 | Commercial and Industrial |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |
Assets, Fair Value | 12,092 | 986
Level 3 | Other Real Estate Owned |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |
Assets, Fair Value | 10,626 | 16,570
Assets Held For Sale |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |
Assets, Fair Value | 9,779 | 14,748
Assets Held For Sale | Level 3 |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |
Assets, Fair Value | $ 9,779 | $ 14,748

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