Loans and Leases - Narrative (Details)	3 Months Ended
	Mar. 31, 2023 USD ($)	Mar. 31, 2022 USD ($) contract	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual loans and leases	$ 87,124,000	$ 66,538,000	$ 103,778,000
Allowance for Loan and Lease Losses, Period Increase (Decrease)	9,300,000
Provision for credit losses	18,500,000	2,000,000
Gross loans and leases held for investment	25,770,912,000		28,726,016,000
Loans and Leases Receivable, Allowance	210,055,000	197,398,000	200,732,000	$ 200,564,000
Loans held for investment, net	25,672,381,000	$ 24,352,072,000	28,609,129,000
Number of loans | contract		14
Pre-Modification Outstanding Recorded Investment		$ 1,378,000
Real Estate Mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual loans and leases	83,056,000	50,163,000	98,402,000
Provision for credit losses	(31,809,000)	11,391,000
Gross loans and leases held for investment	15,436,731,000		15,762,351,000
Loans and Leases Receivable, Allowance	109,483,000	87,228,000	87,309,000	98,624,000
Loans held for investment, net	15,407,611,000	12,509,064,000	15,730,324,000
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual loans and leases	3,543,000	10,402,000	5,210,000
Provision for credit losses	(16,492,000)	(9,436,000)
Gross loans and leases held for investment	5,232,521,000		8,297,182,000
Loans and Leases Receivable, Allowance	37,195,000	57,056,000	52,849,000	$ 48,718,000
Loans held for investment, net	5,229,107,000	$ 8,114,695,000	8,281,962,000
Credit Concentration Risk
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual loans and leases	$ 23,800,000
Credit Concentration Risk | Nonaccrual Loans And Leases Benchmark | Fair Value, Concentration of Risk, All Financial Instruments
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of nonaccrual loans and leases	27.00%
Nonaccrual
Accounts, Notes, Loans and Financing Receivable [Line Items]
Receivable, 90 or more days past due	$ 49,900,000		70,900,000
Receivable, 30-89 days past due	15,100,000		6,800,000
Financing receivable, nonaccrual status, current	22,100,000		26,000,000
Other Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Loans | contract		2
Financing Receivable, Troubled Debt Restructuring, Subsequent Default		$ 78,000
Other Commercial | Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual loans and leases	3,123,000		4,345,000
Loans held for investment, net	1,102,543,000		1,108,451,000
Number of loans | contract		13
Pre-Modification Outstanding Recorded Investment		$ 1,074,000
Venture Capital Loans | Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual loans and leases	0		0
Loans held for investment, net	2,058,237,000		2,033,302,000
Asset-based | Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual loans and leases	420,000		865,000
Loans held for investment, net	$ 2,068,327,000		$ 5,140,209,000