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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	12 Months Ended
	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Mortgage Servicing Rights | Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
Cost to service	$ 90	$ 83
Mortgage Servicing Rights | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
Cost to service	103	108
Mortgage Servicing Rights | Weighted Average
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
Cost to service	96	$ 98
Interests in MSR | Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
Cost to service	78
Interests in MSR | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
Cost to service	84
Interests in MSR | Weighted Average
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
Cost to service	$ 81
Discount rate | Mortgage Servicing Rights | Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
MSR measurement inputs	0.033	0.090
Discount rate | Mortgage Servicing Rights | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
MSR measurement inputs	0.111	0.120
Discount rate | Mortgage Servicing Rights | Weighted Average
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
MSR measurement inputs	0.070	0.094
Discount rate | Interests in MSR | Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
MSR measurement inputs	0.084
Discount rate | Interests in MSR | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
MSR measurement inputs	0.084
Discount rate | Interests in MSR | Weighted Average
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
MSR measurement inputs	0.084
Prepayment rate | Mortgage Servicing Rights | Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
MSR measurement inputs	0.073	0.193
Prepayment rate | Mortgage Servicing Rights | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
MSR measurement inputs	0.159	0.555
Prepayment rate | Mortgage Servicing Rights | Weighted Average
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
MSR measurement inputs	0.094	0.420
Prepayment rate | Interests in MSR | Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
MSR measurement inputs	0.050
Prepayment rate | Interests in MSR | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
MSR measurement inputs	0.144
Prepayment rate | Interests in MSR | Weighted Average
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
MSR measurement inputs	0.091
Delinquency rate | Mortgage Servicing Rights | Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
MSR measurement inputs	0.002	0.000
Delinquency rate | Mortgage Servicing Rights | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
MSR measurement inputs	0.025	0.060
Delinquency rate | Mortgage Servicing Rights | Weighted Average
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
MSR measurement inputs	0.012	0.025
Delinquency rate | Interests in MSR | Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
MSR measurement inputs	0.000
Delinquency rate | Interests in MSR | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
MSR measurement inputs	0.002
Delinquency rate | Interests in MSR | Weighted Average
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
MSR measurement inputs	0.001

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- Definition

Fair value inputs cost to service.

+ References

No definition available.

+ Details

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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=123874694&loc=d3e19207-110258

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