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Significant Unobservable Inputs used in Fair Value Measurement (Detail) - USD ($) $ in Thousands | 6 Months Ended |  |  |
--- | --- | --- | --- | ---
Jun. 30, 2017 | Dec. 31, 2016 | Jun. 30, 2016 | Dec. 31, 2015
Interest rate lock commitments |  |  |  |  |
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items] |  |  |  |  |
Fair value |  | $ 1,027 | $ 982 | $ 10,133 | $ 2,526
Valuation Technique |  | Discounted Cash Flow |  |  |
Weighted Average Closing Ratio |  | 75.04% |  |  |
Mortgage servicing rights |  |  |  |  |
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items] |  |  |  |  |
Weighted Average Discount Rate |  | 10.05% |  |  |
Mortgage servicing rights | Covered loans held for sale |  |  |  |  |
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items] |  |  |  |  |
Fair value |  | $ 220,586 | $ 228,099 | $ 188,331 | $ 243,389
Valuation Technique |  | Discounted Cash Flow |  |  |
Weighted Average Constant Prepayment Rate | [1] | 9.16% |  |  |
[1] | Represents annualized loan repayment rate assumptions.

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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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- 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 Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + 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 (c) -URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258 + 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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