Loans and Allowance for Credit Losses for Loans - Summary of Allocation of Allowance for Loan Losses and Related Loans by Loan Portfolio Segment Disaggregated Based on Allowance Measurement Methodology (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Mar. 31, 2024	Dec. 31, 2023	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2022
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually evaluated for credit losses	$ 83,619		$ 74,215
Collectively evaluated for credit losses	435,691		371,865
Total	519,310	$ 469,248	446,080	$ 436,432	$ 436,898	$ 458,655
Individually evaluated for credit losses	339,877		264,678
Collectively evaluated for credit losses	49,971,825		49,945,617
Total	50,311,702		50,210,295
Commercial and industrial
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually evaluated for credit losses	50,494		55,993
Collectively evaluated for credit losses	98,749		77,366
Total	149,243	138,593	133,359	128,245	127,992	139,941
Individually evaluated for credit losses	125,186		96,827
Collectively evaluated for credit losses	9,353,961		9,133,716
Total	9,479,147		9,230,543
Commercial Real Estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually evaluated for credit losses	33,096		17,987
Collectively evaluated for credit losses	267,997		231,611
Total	301,093	265,847	249,598	239,695	243,332	259,408
Individually evaluated for credit losses	195,654		145,419
Collectively evaluated for credit losses	31,573,192		31,824,628
Total	31,768,846		31,970,047
Residential Mortgage
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually evaluated for credit losses	29		235
Collectively evaluated for credit losses	47,668		42,722
Total	47,697	44,377	42,957	44,153	41,708	39,020
Individually evaluated for credit losses	18,721		21,843
Collectively evaluated for credit losses	5,608,392		5,547,167
Total	5,627,113		5,569,010
Consumer loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually evaluated for credit losses	0		0
Collectively evaluated for credit losses	21,277		20,166
Total	21,277	$ 20,431	20,166	$ 24,339	$ 23,866	$ 20,286
Individually evaluated for credit losses	316		589
Collectively evaluated for credit losses	3,436,280		3,440,106
Total	$ 3,436,596		$ 3,440,695