NON-CONSOLIDATED VARIABLE INTEREST ENTITIES (VIEs) AND SERVICING ASSETS - Key Economic Assumptions Used in Determining Fair Value at Time of Sale of Loans (Detail)	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Weighted Average [Member] | Conventional Loan [Member]
Assumption For Fair Value On Securitization Date Of Interests Continued To Be Held By Transferor Servicing Assets Or Liabilities [Line Items]
Constant prepayment rate	7.40%	6.60%
Discount rate	9.50%	9.80%
Weighted Average [Member] | Conventional Non Conforming Mortgage Loans [Member]
Assumption For Fair Value On Securitization Date Of Interests Continued To Be Held By Transferor Servicing Assets Or Liabilities [Line Items]
Constant prepayment rate	5.90%	6.00%
Discount rate	13.00%	12.40%
Weighted Average [Member] | Government-guaranteed mortgage loans [Member]
Assumption For Fair Value On Securitization Date Of Interests Continued To Be Held By Transferor Servicing Assets Or Liabilities [Line Items]
Constant prepayment rate	6.60%	6.60%
Discount rate	11.50%	11.80%
Maximum [Member] | Conventional Loan [Member]
Assumption For Fair Value On Securitization Date Of Interests Continued To Be Held By Transferor Servicing Assets Or Liabilities [Line Items]
Constant prepayment rate	16.00%	18.40%
Discount rate	9.50%	10.00%
Maximum [Member] | Conventional Non Conforming Mortgage Loans [Member]
Assumption For Fair Value On Securitization Date Of Interests Continued To Be Held By Transferor Servicing Assets Or Liabilities [Line Items]
Constant prepayment rate	9.00%	21.90%
Discount rate	14.00%	14.50%
Maximum [Member] | Government-guaranteed mortgage loans [Member]
Assumption For Fair Value On Securitization Date Of Interests Continued To Be Held By Transferor Servicing Assets Or Liabilities [Line Items]
Constant prepayment rate	11.60%	18.30%
Discount rate	11.50%	12.00%
Minimum [Member] | Conventional Loan [Member]
Assumption For Fair Value On Securitization Date Of Interests Continued To Be Held By Transferor Servicing Assets Or Liabilities [Line Items]
Constant prepayment rate	3.80%	3.40%
Discount rate	9.50%	9.50%
Minimum [Member] | Conventional Non Conforming Mortgage Loans [Member]
Assumption For Fair Value On Securitization Date Of Interests Continued To Be Held By Transferor Servicing Assets Or Liabilities [Line Items]
Constant prepayment rate	2.10%	3.80%
Discount rate	11.50%	11.50%
Minimum [Member] | Government-guaranteed mortgage loans [Member]
Assumption For Fair Value On Securitization Date Of Interests Continued To Be Held By Transferor Servicing Assets Or Liabilities [Line Items]
Constant prepayment rate	4.80%	4.80%
Discount rate	11.50%	11.50%