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Fair Value Accounting and Measurement Fair Value, quantitative inputs to Level 3 measurements (Details) - Fair Value, Measurements, Nonrecurring [Member] - USD ($) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2016 | Dec. 31, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items] |  |
Impaired loans | $ 3,787 | $ 758
Fair Value, Inputs, Level 3 [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items] |  |
Impaired loans | 3,787 | 758
Other Real Estate Owned, Fair Value Disclosure | 4,388 | 4,524
Real Estate Collateral [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items] |  |
Impaired loans |  | 380
Other Collateral [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items] |  |
Impaired loans |  | $ 378
Not Collateral-Dependent [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items] |  |
Impaired loans | 1,539 |
Real Estate Collateral [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items] |  |
Impaired loans | $ 2,248 |
Income Approach Valuation Technique [Member] | Minimum [Member] | Impaired Loans [Member] | Fair Value, Inputs, Level 3 [Member] | Not Collateral-Dependent [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items] |  |
Fair Value Inputs, Discount Rate | 4.50% |
Income Approach Valuation Technique [Member] | Maximum [Member] | Impaired Loans [Member] | Fair Value, Inputs, Level 3 [Member] | Not Collateral-Dependent [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items] |  |
Fair Value Inputs, Discount Rate | 6.50% |
Income Approach Valuation Technique [Member] | Weighted Average [Member] | Impaired Loans [Member] | Fair Value, Inputs, Level 3 [Member] | Not Collateral-Dependent [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items] |  |
Fair Value Inputs, Discount Rate | 5.26% |

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bbb) -URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258 + Details
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