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Fair Value Measurement - Summary of Unobservable Inputs Used in Fair Value Measurements on Recurring Basis Categorized Within Level 3 of Fair Value Hierarchy (Details) - Fair Value, Measurements, Recurring - Level 3 | 12 Months Ended
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Dec. 31, 2017
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |
Impact to Valuation from an Increased or Higher Input Value | Decrease
Minimum |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |
Discount rate | 9.90%
Expected weighted average loan life | 2 months 12 days
Maximum |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |
Discount rate | 18.40%
Expected weighted average loan life | 8 years 2 months 12 days
Weighted Average |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |
Discount rate | 13.80%
Expected weighted average loan life | 5 years 9 months 18 days
Obligations of States, Municipalities, and Political Subdivisions |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |
Valuation Technique | Discounted cash flow
Impact to Valuation from an Increased or Higher Input Value | Decrease
Obligations of States, Municipalities, and Political Subdivisions | Minimum |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |
Probability of default | 2.20%
Obligations of States, Municipalities, and Political Subdivisions | Maximum |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |
Probability of default | 2.40%
Obligations of States, Municipalities, and Political Subdivisions | Weighted Average |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |
Probability of default | 2.30%
Single Issuer Trust Preferred |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |
Valuation Technique | Discounted cash flow
Impact to Valuation from an Increased or Higher Input Value | Decrease
Single Issuer Trust Preferred | Minimum |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |
Probability of default | 7.50%
Single Issuer Trust Preferred | Maximum |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |
Probability of default | 9.90%
Single Issuer Trust Preferred | Weighted Average |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |
Probability of default | 8.90%
Servicing Assets |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |
Valuation Technique | Discounted cash flow
Impact to Valuation from an Increased or Higher Input Value | Decrease
Servicing Assets | Minimum |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |
Prepayment speeds | 1.60%
Servicing Assets | Maximum |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |
Prepayment speeds | 9.90%
Servicing Assets | Weighted Average |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |
Prepayment speeds | 8.60%

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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 Period the instrument, asset or liability is expected to be outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + 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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- 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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- Definition Rate at which loans or a loan portfolio are expected to prepay principal balances, used as an input to measure fair value. + 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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- Definition Percentage of likelihood a loan will not be repaid and instead default, used as an input to measure fair value. + 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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- Definition Description of the changes in significant assumptions used by management to measure fair value. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13433-108611 + Details
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- Definition Description of the inputs and valuation technique(s) used to measure fair value. + 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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