INVESTMENTS - Narrative (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Mar. 31, 2022
Schedule of Investments [Line Items]
Amortized cost of debt securities transferred to held-to-maturity			$ 305,600
Fair value of debt securities transferred to held-to-maturity			289,400
Unrealized losses on debt securities transferred to held-to-maturity			$ 16,200
Book value of debt securities pledged as collateral	$ 1,456,984	$ 1,626,295
Asset Pledged as Collateral | Deposits
Schedule of Investments [Line Items]
Book value of debt securities pledged as collateral	729,000	$ 533,900
Collateralized mortgage obligations
Schedule of Investments [Line Items]
Mortgage-backed securities	441,200
Mortgage-backed securities
Schedule of Investments [Line Items]
Mortgage-backed securities	562,700
SBA asset-backed securities
Schedule of Investments [Line Items]
Mortgage-backed securities	$ 39,900