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	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Allowance for loan losses:
Individually evaluated for credit losses	$ 74,215	$ 86,594
Collectively evaluated for credit losses	371,865	372,061
Total	446,080	458,655	$ 359,202
Loans:
Individually evaluated for credit losses	264,678	374,093
Collectively evaluated for credit losses	49,945,617	46,543,107
Total	50,210,295	46,917,200
Commercial and Industrial
Allowance for loan losses:
Individually evaluated for credit losses	55,993	68,745
Collectively evaluated for credit losses	77,366	71,196
Total	133,359	139,941	103,090
Loans:
Individually evaluated for credit losses	96,827	117,644
Collectively evaluated for credit losses	9,133,716	8,687,186
Total	9,230,543	8,804,830
Commercial real estate
Allowance for loan losses:
Individually evaluated for credit losses	17,987	13,174
Collectively evaluated for credit losses	231,611	246,234
Total	249,598	259,408	217,490
Loans:
Individually evaluated for credit losses	145,419	213,522
Collectively evaluated for credit losses	31,824,628	29,219,346
Total	31,970,047	29,432,868
Residential Mortgage
Allowance for loan losses:
Individually evaluated for credit losses	235	337
Collectively evaluated for credit losses	42,722	38,683
Total	42,957	39,020	25,120
Loans:
Individually evaluated for credit losses	21,843	28,869
Collectively evaluated for credit losses	5,547,167	5,335,681
Total	5,569,010	5,364,550
Home equity
Allowance for loan losses:
Individually evaluated for credit losses	0	4,338
Collectively evaluated for credit losses	20,166	15,948
Total	20,166	20,286	$ 13,502
Loans:
Individually evaluated for credit losses	589	14,058
Collectively evaluated for credit losses	3,440,106	3,300,894
Total	$ 3,440,695	$ 3,314,952