DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES - Summary of Fair Value of Derivative Instruments and Location in Statement of Financial Condition (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Derivatives Fair Value [Line Items]
Other Assets	$ 171,066	$ 166,682
Accrued Liabilities and Other Liabilities	129,907	145,905
Not Designated as Hedging Instrument, Economic Hedge [Member]
Derivatives Fair Value [Line Items]
Derivative Assets	1,018	312
Derivative Liabilities	1,000	324
Not Designated as Hedging Instrument, Economic Hedge [Member] | Sale of TBA GNMA MBS pools
Derivatives Fair Value [Line Items]
Other Assets	0	7
Accrued Liabilities and Other Liabilities	383	19
Not Designated as Hedging Instrument, Economic Hedge [Member] | Forward loan sales commitments [Member]
Derivatives Fair Value [Line Items]
Other Assets	12	0
Accrued Liabilities and Other Liabilities	0	0
Not Designated as Hedging Instrument, Economic Hedge [Member] | Interest Rate Lock Commitments [Member]
Derivatives Fair Value [Line Items]
Other Assets	383	0
Accrued Liabilities and Other Liabilities	0	0
Not Designated as Hedging Instrument, Economic Hedge [Member] | Interest Rate Cap [Member] | Written [Member]
Derivatives Fair Value [Line Items]
Other Assets	0	0
Accrued Liabilities and Other Liabilities	617	305
Not Designated as Hedging Instrument, Economic Hedge [Member] | Interest Rate Cap [Member] | Purchase [Member]
Derivatives Fair Value [Line Items]
Other Assets	623	305
Accrued Liabilities and Other Liabilities	$ 0	$ 0