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, 2023	Mar. 31, 2023	Dec. 31, 2022	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2021
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually evaluated for credit losses	$ 61,094		$ 86,594
Collectively evaluated for credit losses	375,338		372,061
Total	436,432	$ 436,898	458,655	$ 468,819	$ 362,510	$ 359,202
Individually evaluated for credit losses	231,547		374,093
Collectively evaluated for credit losses	49,645,701		46,543,107
Total	49,877,248		46,917,200
Commercial and industrial
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually evaluated for credit losses	54,311		68,745
Collectively evaluated for credit losses	73,934		71,196
Total	128,245	127,992	139,941	144,539	101,203	103,090
Individually evaluated for credit losses	77,364		117,644
Collectively evaluated for credit losses	9,209,945		8,687,186
Total	9,287,309		8,804,830
Commercial Real Estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually evaluated for credit losses	6,749		13,174
Collectively evaluated for credit losses	232,946		246,234
Total	239,695	243,332	259,408	277,227	219,949	217,490
Individually evaluated for credit losses	138,032		213,522
Collectively evaluated for credit losses	31,470,801		29,219,346
Total	31,608,833		29,432,868
Residential Mortgage
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually evaluated for credit losses	34		337
Collectively evaluated for credit losses	44,119		38,683
Total	44,153	41,708	39,020	29,889	28,189	25,120
Individually evaluated for credit losses	16,151		28,869
Collectively evaluated for credit losses	5,544,205		5,335,681
Total	5,560,356		5,364,550
Consumer
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually evaluated for credit losses	0		4,338
Collectively evaluated for credit losses	24,339		15,948
Total	24,339	$ 23,866	20,286	$ 17,164	$ 13,169	$ 13,502
Individually evaluated for credit losses	0		14,058
Collectively evaluated for credit losses	3,420,750		3,300,894
Total	$ 3,420,750		$ 3,314,952