Loans and Allowance for Credit Losses for Loans - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non covered loans net of unearned discount and deferred loan fees	$ 120,500,000	$ 78,500,000
Payments to acquire loans held-for-investment	5,900,000,000
Non covered loans	98,600,000
Accrued interest	175,900,000	83,700,000
Sales of loans	0	0
Loans	46,917,200,000	34,153,657,000
Net loans	46,458,545,000	33,794,455,000
Allowance for loan losses	$ 458,655,000	359,202,000	$ 340,243,000
Combined loan-to-value ratio home equity loan	80.00%
Accrued interest on non-accrual loans	$ 21,700,000	7,100,000	6,200,000
Number of consecutive months for performing restructured loans to be put on accrual status	6 months
TDRs not reported as non-accrual loans	$ 77,500,000	71,300,000
Non-performing TDRs	124,000,000	117,200,000
Specific reserves for loan losses	63,000,000	29,100,000
Post-Modification Outstanding Recorded Investment	128,269,000	106,234,000
Loan charge-offs related to loans modified as TDRs	$ 26,200,000	6,000,000
Financing Receivable, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration]	Accrued interest receivable
Commitments under unused lines of credit—credit card
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unsecured loans	$ 16,800,000	12,800,000
Residential mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	5,364,550,000	4,545,064,000
Allowance for loan losses	39,020,000	25,120,000	28,873,000
Post-Modification Outstanding Recorded Investment	3,209,000	9,578,000
Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unsecured loans	555,300,000	1,000,000,000
Loans	8,804,830,000	5,847,551,000
Allowance for loan losses	139,941,000	103,090,000	131,070,000
Post-Modification Outstanding Recorded Investment	90,259,000	48,764,000
Commercial and industrial | Tax Medallion
Accounts, Notes, Loans and Financing Receivable [Line Items]
Net loans	66,500,000
Allowance for loan losses	42,200,000
Commercial and industrial | Commercial and industrial PPP loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	33,580,000	435,950,000
Home equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unsecured loans	63,800,000	54,000,000
Loans	3,314,952,000	2,970,976,000
Allowance for loan losses	20,286,000	13,502,000	$ 16,187,000
Post-Modification Outstanding Recorded Investment	$ 116,000	$ 161,000