Shareholders' Equity And Earnings Per Share (Other Comprehensive Income Reclassified from AOCI) (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
(Losses) gains on investment securities, net	$ 11	$ 350	$ 262	$ 1,144
Income tax expense	(57,080)	(40,605)	(140,517)	(133,357)
Interest on deposits	45,916	19,305	79,755	71,547
Interest on junior subordinated debentures	2,809	2,744	6,426	8,172
Net income	142,961	109,137	364,865	367,394
Reclassification Out of Accumulated Other Comprehensive Income | Accumulated unrealized (losses) gains on securities
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
(Losses) gains on investment securities, net	12	350	262	1,144
Income before taxes	12	350	262	1,144
Income tax expense	(3)	(94)	(70)	(307)
Net income	9	256	192	837
Reclassification Out of Accumulated Other Comprehensive Income | Accumulated unrealized gains on derivative instruments
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Income before taxes	5,451	(6,780)	(914)	(20,342)
Income tax expense	(1,453)	1,807	244	5,421
Interest on deposits	(5,563)	4,947	(87)	14,898
Interest on other borrowings	112	636	1,001	1,958
Interest on junior subordinated debentures	0	1,197	0	3,486
Net income	$ 3,998	$ (4,973)	$ (670)	$ (14,921)