INVESTMENT SECURITIES - Additional Information (Detail) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024 USD ($) security entity	Sep. 30, 2023 USD ($) security contract	Sep. 30, 2024 USD ($) security	Sep. 30, 2023 USD ($) contract security entity	Dec. 31, 2023 USD ($) security
Debt Securities, Available-for-sale [Line Items]
Proceeds from sales of investment securities available for sale	$ 100	$ 4,100	$ 240,847	$ 4,075
Number of available-for-sale investment securities, unrealized loss position, less than twelve month category | security	21		21
Number of available-for-sale investment securities, unrealized loss position, twelve month or more category | security	92		92
Number of asset-backed securities with deterioration in future estimated cash flows | security	2	4	2	4
Number of corporate notes with deterioration in future estimated cash flows | security	20	12	20	12
Number of available-for-sale investment securities, unrealized loss position | security	113		113		119
Debt securities, available for sale	$ 2,377,733		$ 2,377,733		$ 2,376,860
Net gain on sale of loans	0	$ 200	(200)	$ 200
Investment securities held to maturity	1,064,437		1,064,437		1,103,170
Servicing assets	2,100	$ 3,800	2,100	$ 3,800
Number of VIE Counterparties | contract		1		1
Variable Interest Entity, Not Primary Beneficiary
Debt Securities, Available-for-sale [Line Items]
Investment securities held to maturity	160,000	$ 436,800	160,000	$ 436,800
Consumer Loan, Held-For-Sale
Debt Securities, Available-for-sale [Line Items]
Net gain on sale of loans	300	$ 1,200	300	1,200
Consumer Loan, Held-For-Sale | Personal And Other Installment Loans
Debt Securities, Available-for-sale [Line Items]
Carrying value of consumer loans sold	$ 202,500		202,500	$ 556,700
Number of VIEs | entity	2			2
Consumer Loan, Held-For-Sale | Other Installment Loans
Debt Securities, Available-for-sale [Line Items]
Financing receivable, sale	$ 53,000		53,000	$ 154,000
Asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Debt securities, available for sale	37,670		37,670		92,629
Investment securities held to maturity	538,832		538,832		575,990
Asset Pledged as Collateral
Debt Securities, Available-for-sale [Line Items]
Debt securities, available for sale	1,300,000		1,300,000		1,200,000
Debt securities	$ 412,300		$ 412,300		$ 398,400