NON-CONSOLIDATED VARIABLE INTEREST ENTITIES AND SERVICING ASSETS - Key Economic Assumptions Used in Determining Fair Value at Time of Sale of Loans (Detail)	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Government Guaranteed Mortgage Loans [Member] | Maximum [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	7.60%	9.20%
Discount rate	12.00%	11.50%
Government Guaranteed Mortgage Loans [Member] | Minimum [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	6.10%	7.90%
Discount rate	11.50%	11.50%
Conventional Loan [Member] | Maximum [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	8.00%	9.00%
Discount rate	10.00%	9.50%
Conventional Loan [Member] | Minimum [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	6.50%	7.90%
Discount rate	9.50%	9.50%
Conventional Non Conforming Mortgage Loans [Member] | Maximum [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	14.10%	14.40%
Discount rate	14.30%	13.80%
Conventional Non Conforming Mortgage Loans [Member] | Minimum [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	10.60%	12.90%
Discount rate	13.80%	13.80%