Revenue from Contracts with Customers - Summary of Sources of Noninterest Income that are Subject to Revenue Recognition Accounting Guidance (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Disaggregation Of Revenue [Line Items]
Brokerage services income	$ 26,988	$ 21,086	$ 76,155	$ 65,414
Other revenues from operations:
Total other income	559,581	563,079	1,949,885	1,675,066
Service Charges on Deposit Accounts [Member]
Disaggregation Of Revenue [Line Items]
Revenue from contract with customer	121,360	115,213	353,603	340,890
Trust Income [Member]
Disaggregation Of Revenue [Line Items]
Revenue from contract with customer	155,092	186,577	521,357	545,874
ASU 2014-09 [Member]
Disaggregation Of Revenue [Line Items]
Brokerage services income	26,988	21,086	76,155	65,414
Other revenues from operations:
Merchant discount and credit card fees	42,841	42,504	122,005	117,108
Other	15,289	26,048	46,229	77,317
Total other income	361,570	391,428	1,119,349	1,146,603
ASU 2014-09 [Member] | Service Charges on Deposit Accounts [Member]
Disaggregation Of Revenue [Line Items]
Revenue from contract with customer	121,360	115,213	353,603	340,890
ASU 2014-09 [Member] | Trust Income [Member]
Disaggregation Of Revenue [Line Items]
Revenue from contract with customer	155,092	186,577	521,357	545,874
ASU 2014-09 [Member] | Business Banking [Member]
Other revenues from operations:
Merchant discount and credit card fees	17,021	16,234	48,206	45,874
Total other income	38,793	35,511	110,355	99,455
ASU 2014-09 [Member] | Business Banking [Member] | Service Charges on Deposit Accounts [Member]
Disaggregation Of Revenue [Line Items]
Revenue from contract with customer	21,749	19,277	62,097	53,581
ASU 2014-09 [Member] | Business Banking [Member] | Trust Income [Member]
Disaggregation Of Revenue [Line Items]
Revenue from contract with customer	23		52
ASU 2014-09 [Member] | Commercial Banking [Member]
Other revenues from operations:
Merchant discount and credit card fees	19,494	17,731	53,056	48,044
Other	5,839	9,878	16,441	13,040
Total other income	56,570	58,015	159,437	146,890
ASU 2014-09 [Member] | Commercial Banking [Member] | Service Charges on Deposit Accounts [Member]
Disaggregation Of Revenue [Line Items]
Revenue from contract with customer	31,237	30,406	89,940	85,806
ASU 2014-09 [Member] | Commercial Real Estate [Member]
Other revenues from operations:
Merchant discount and credit card fees	1,171	1,104	3,406	2,836
Other	942	1,961	3,460	8,228
Total other income	6,664	6,748	20,029	21,967
ASU 2014-09 [Member] | Commercial Real Estate [Member] | Service Charges on Deposit Accounts [Member]
Disaggregation Of Revenue [Line Items]
Revenue from contract with customer	4,551	3,683	13,163	10,903
ASU 2014-09 [Member] | Discretionary Portfolio [Member]
Other revenues from operations:
Other	13	904	51	2,468
Total other income	13	904	51	2,468
ASU 2014-09 [Member] | Residential Mortgage Banking [Member]
Other revenues from operations:
Other	125	558	676	3,413
Total other income	125	558	676	3,413
ASU 2014-09 [Member] | Retail Banking [Member]
Other revenues from operations:
Merchant discount and credit card fees	4,795	6,874	16,345	19,408
Other	7,605	3,980	22,679	16,752
Total other income	74,411	72,077	222,165	222,150
ASU 2014-09 [Member] | Retail Banking [Member] | Service Charges on Deposit Accounts [Member]
Disaggregation Of Revenue [Line Items]
Revenue from contract with customer	62,011	61,223	183,141	185,990
ASU 2014-09 [Member] | All Other [Member]
Disaggregation Of Revenue [Line Items]
Brokerage services income	26,988	21,086	76,155	65,414
Other revenues from operations:
Merchant discount and credit card fees	360	561	992	946
Other	765	8,767	2,922	33,416
Total other income	184,994	217,615	606,636	650,260
ASU 2014-09 [Member] | All Other [Member] | Service Charges on Deposit Accounts [Member]
Disaggregation Of Revenue [Line Items]
Revenue from contract with customer	1,812	624	5,262	4,610
ASU 2014-09 [Member] | All Other [Member] | Trust Income [Member]
Disaggregation Of Revenue [Line Items]
Revenue from contract with customer	$ 155,069	$ 186,577	$ 521,305	$ 545,874