ACCUMULATED OTHER COMPREHENSIVE INCOME/ (LOSS) - Reclassification Adjustments Out of Accumulated Other Comprehensive Income (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Accumulated Other Comprehensive Income (Loss) [Line Items]
Investment securities losses	$ 0	$ 0	$ (345)
Interest and dividends on investment securities	672,272	637,524	495,667
Recognized net actuarial loss	0	526	783
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement	0	(8,157)	0
Income before taxes	48,961	164,135	222,358
Tax expense (benefit)	(29,026)	(41,291)	(56,059)
Net income	19,935	122,844	166,299
Reclassification out of Accumulated Other Comprehensive Income | Unrealized Gains/ (Losses) on Investments Available-for-Sale
Accumulated Other Comprehensive Income (Loss) [Line Items]
Investment securities losses	0	0	(345)
Income before taxes	0	0	(345)
Tax expense (benefit)	0	0	88
Net income	0	0	(257)
Reclassification out of Accumulated Other Comprehensive Income | Unrealized Losses on Debt Securities Transferred from Available-for-Sale to Held-to-Maturity
Accumulated Other Comprehensive Income (Loss) [Line Items]
Interest and dividends on investment securities	(1,498)	(1,726)	(2,245)
Income before taxes	(1,498)	(1,726)	(2,245)
Tax expense (benefit)	368	452	598
Net income	(1,130)	(1,274)	(1,647)
Reclassification out of Accumulated Other Comprehensive Income | Accumulated Defined Benefit Plans Adjustment, Net Gain (Loss) Attributable to Parent
Accumulated Other Comprehensive Income (Loss) [Line Items]
Recognized net actuarial loss	0	(526)	(783)
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement	0	(8,157)	0
Reclassification out of Accumulated Other Comprehensive Income | Defined Benefit Pension Plan
Accumulated Other Comprehensive Income (Loss) [Line Items]
Income before taxes	0	(8,683)	(783)
Tax expense (benefit)	0	2,212	199
Net income	$ 0	$ (6,471)	$ (584)