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, 2025	Mar. 31, 2025	Dec. 31, 2024	Jun. 30, 2024	Mar. 31, 2024	Dec. 31, 2023
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually evaluated for credit losses	$ 55,443		$ 75,855
Collectively evaluated for credit losses	524,057		482,995
Total	579,500	$ 578,200	558,850	$ 519,310	$ 469,248	$ 446,080
Individually evaluated for credit losses	326,988		329,702
Collectively evaluated for credit losses	49,064,432		48,470,009
Total	49,391,420		48,799,711
Commercial and industrial
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually evaluated for credit losses	46,395		59,603
Collectively evaluated for credit losses	127,020		113,399
Total	173,415	184,700	173,002	149,243	138,593	133,359
Individually evaluated for credit losses	114,302		131,898
Collectively evaluated for credit losses	10,755,734		9,799,502
Total	10,870,036		9,931,400
Commercial Real Estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually evaluated for credit losses	9,023		16,225
Collectively evaluated for credit losses	325,956		287,923
Total	334,979	321,662	304,148	301,093	265,847	249,598
Individually evaluated for credit losses	182,046		172,666
Collectively evaluated for credit losses	28,643,874		29,472,292
Total	28,825,920		29,644,958
Residential Mortgage
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually evaluated for credit losses	25		27
Collectively evaluated for credit losses	48,805		58,868
Total	48,830	48,906	58,895	47,697	44,377	42,957
Individually evaluated for credit losses	29,317		23,797
Collectively evaluated for credit losses	5,680,654		5,608,719
Total	5,709,971		5,632,516
Consumer loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually evaluated for credit losses	0		0
Collectively evaluated for credit losses	22,276		22,805
Total	22,276	$ 22,932	22,805	$ 21,277	$ 20,431	$ 20,166
Individually evaluated for credit losses	1,323		1,341
Collectively evaluated for credit losses	3,984,170		3,589,496
Total	$ 3,985,493		$ 3,590,837