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FAIR VALUE MEASUREMENTS - Information about Significant Unobservable Inputs Used for Recurring Fair Value Measurements for Level 3 MSRs (Detail) - Fair Value, Measurements, Recurring - Level 3 - Mortgage Servicing Rights | 12 Months Ended
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Dec. 31, 2019 USD ($) | Dec. 31, 2018 USD ($)
Minimum |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |
Unobservable input, cost to service | $ 81 | $ 82
Maximum |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |
Unobservable input, cost to service | 135 | 138
Weighted Average |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |
Unobservable input, cost to service | $ 107 | $ 110
Discount Rate | Minimum |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |
MSR measurement inputs | 0.090 | 0.090
Discount Rate | Maximum |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |
MSR measurement inputs | 0.120 | 0.120
Discount Rate | Weighted Average |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |
MSR measurement inputs | 0.093 | 0.094
Prepayment Rate | Minimum |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |
MSR measurement inputs | 0.063 | 0.047
Prepayment Rate | Maximum |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |
MSR measurement inputs | 0.266 | 0.139
Prepayment Rate | Weighted Average |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |
MSR measurement inputs | 0.137 | 0.080
Delinquency Rate | Minimum |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |
MSR measurement inputs | 0.000 | 0.000
Delinquency Rate | Maximum |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |
MSR measurement inputs | 0.040 | 0.050
Delinquency Rate | Weighted Average |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |
MSR measurement inputs | 0.022 | 0.023

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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 Value of input used to measure servicing asset. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bbb)(2) -URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258 + Details
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