INCOME TAXES - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Sep. 01, 2020
Income Tax Contingency [Line Items]
Maximum corporate tax rate	37.50%	37.50%	37.50%
Net deferred tax asset	$ 150,127	$ 155,584
Valuation allowance	139,188	185,506
Deferred tax asset not subject to expiration period	253,900	279,900
Income tax expense	$ 94,572	142,512	$ 146,792
Minimum percentage of bank net taxable income for paying income tax at normal rate	20.00%
Current income tax expense	$ 88,467	88,296	28,469
NOL and capital loss carryforward	48,633	72,485
Year 2024 Through Year 2037 [Member]
Income Tax Contingency [Line Items]
NOL and capital loss carryforward	35,400
Year 2024 [Member]
Income Tax Contingency [Line Items]
NOL and capital loss carryforward	15,300
Santander [Member]
Income Tax Contingency [Line Items]
UTBs				$ 800
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense	200
Benefit recognized from expiration of uncertain tax positions acquired	300
U S [Member]
Income Tax Contingency [Line Items]
Income tax expense	9,900	10,300	6,800
Subsidiaries [Member]
Income Tax Contingency [Line Items]
Net deferred tax asset	150,100	155,600
Valuation allowance	111,400	149,500
Parent Company [Member]
Income Tax Contingency [Line Items]
Valuation allowance	27,800
Income tax expense	$ 3,126	$ 3,448	$ 2,854
Domestic Country [Member] | Subsidiaries [Member]
Income Tax Contingency [Line Items]
Dividend received deduction	100.00%
Domestic Country [Member] | Other taxable domestic corporations [Member]
Income Tax Contingency [Line Items]
Dividend received deduction	85.00%