SEGMENT INFORMATION - Reconciliation of Reportable Segment Financial Information (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Net Income (Loss):
Income before income taxes	$ 108,990	$ 106,631	$ 312,562	$ 341,054
Income tax expense	26,968	32,028	89,187	109,156
Net income	82,022	74,603	223,375	231,898
Segment Reconciling Items [Member]
Net Income (Loss):
Segment income	151,198	147,438	437,957	454,291
Other operating expenses	42,208	40,807	125,395	113,237
Income before income taxes	108,990	106,631	312,562	341,054
Income tax expense	26,968	32,028	89,187	109,156
Net income	82,022	74,603	223,375	231,898
Average assets:
Total average earning assets for segments	18,063,606	18,311,378	17,902,642	18,830,683
Average non-earning assets	832,374	835,740	845,837	873,911
Total consolidated average assets	$ 18,895,980	$ 19,147,118	$ 18,748,479	$ 19,704,594