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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	9 Months Ended	12 Months Ended
	Sep. 30, 2022 USD ($)	Dec. 31, 2021 USD ($)
MSR held directly | Minimum
Fair Value, Option, Quantitative Disclosures [Line Items]
Cost to service	$ 88	$ 90
MSR held directly | Maximum
Fair Value, Option, Quantitative Disclosures [Line Items]
Cost to service	108	103
MSR held directly | Weighted Average
Fair Value, Option, Quantitative Disclosures [Line Items]
Cost to service	$ 94	96
Interests in MSR | Minimum
Fair Value, Option, Quantitative Disclosures [Line Items]
Cost to service		78
Interests in MSR | Maximum
Fair Value, Option, Quantitative Disclosures [Line Items]
Cost to service		84
Interests in MSR | Weighted Average
Fair Value, Option, Quantitative Disclosures [Line Items]
Cost to service		$ 81
Discount rate | MSR held directly | Minimum
Fair Value, Option, Quantitative Disclosures [Line Items]
MSR measurement inputs	0.066	0.033
Discount rate | MSR held directly | Maximum
Fair Value, Option, Quantitative Disclosures [Line Items]
MSR measurement inputs	0.095	0.111
Discount rate | MSR held directly | Weighted Average
Fair Value, Option, Quantitative Disclosures [Line Items]
MSR measurement inputs	0.087	0.070
Discount rate | Interests in MSR | Minimum
Fair Value, Option, Quantitative Disclosures [Line Items]
MSR measurement inputs		0.084
Discount rate | Interests in MSR | Maximum
Fair Value, Option, Quantitative Disclosures [Line Items]
MSR measurement inputs		0.084
Discount rate | Interests in MSR | Weighted Average
Fair Value, Option, Quantitative Disclosures [Line Items]
MSR measurement inputs		0.084
Prepayment rate | MSR held directly | Minimum
Fair Value, Option, Quantitative Disclosures [Line Items]
MSR measurement inputs	0.048	0.073
Prepayment rate | MSR held directly | Maximum
Fair Value, Option, Quantitative Disclosures [Line Items]
MSR measurement inputs	0.080	0.159
Prepayment rate | MSR held directly | Weighted Average
Fair Value, Option, Quantitative Disclosures [Line Items]
MSR measurement inputs	0.053	0.094
Prepayment rate | Interests in MSR | Minimum
Fair Value, Option, Quantitative Disclosures [Line Items]
MSR measurement inputs		0.050
Prepayment rate | Interests in MSR | Maximum
Fair Value, Option, Quantitative Disclosures [Line Items]
MSR measurement inputs		0.144
Prepayment rate | Interests in MSR | Weighted Average
Fair Value, Option, Quantitative Disclosures [Line Items]
MSR measurement inputs		0.091
Delinquency rate | MSR held directly | Minimum
Fair Value, Option, Quantitative Disclosures [Line Items]
MSR measurement inputs	0.001	0.002
Delinquency rate | MSR held directly | Maximum
Fair Value, Option, Quantitative Disclosures [Line Items]
MSR measurement inputs	0.041	0.025
Delinquency rate | MSR held directly | Weighted Average
Fair Value, Option, Quantitative Disclosures [Line Items]
MSR measurement inputs	0.009	0.012
Delinquency rate | Interests in MSR | Minimum
Fair Value, Option, Quantitative Disclosures [Line Items]
MSR measurement inputs		0.000
Delinquency rate | Interests in MSR | Maximum
Fair Value, Option, Quantitative Disclosures [Line Items]
MSR measurement inputs		0.002
Delinquency rate | Interests in MSR | Weighted Average
Fair Value, Option, Quantitative Disclosures [Line Items]
MSR measurement inputs		0.001

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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 https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258

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