Loans Receivable, Including Loans Held For Sale - Narrative (Details) loan in Thousands	3 Months Ended
	Mar. 31, 2023 USD ($) loan	Mar. 31, 2022 USD ($)	Dec. 31, 2022 USD ($)
Receivable [Line Items]
Total loans	$ 1,151,445,000		$ 982,008,000
Increase in loans held for sale	4,388,701,000	$ 3,072,573,000
Loans past due 90 days or more	15,790,000		15,940,000
Nonaccrual loans	788,000		788,000
Other borrowings	31,692,000		41,682,000
Liabilities Associated with PPP Loan
Receivable [Line Items]
Other borrowings	31,692,000
Commercial and industrial
Receivable [Line Items]
Total loans	1,020,600,000		857,817,000
Loans past due 90 days or more	10,620,000		11,260,000
Nonaccrual loans	788,000		788,000
Consumer loans
Receivable [Line Items]
Total loans	129,575,000		123,204,000
Loans past due 90 days or more	5,170,000		4,680,000
Nonaccrual loans	0		0
Asset Pledged as Collateral
Receivable [Line Items]
Total loans	438,244,000		323,740,000
Loan Modifications, COVID-19
Receivable [Line Items]
Total loans	$ 2,122,000
Short-term deferments on loan balances | loan	4,554
Percentage of total loan balances	0.18%
Small Business Administration (SBA), CARES Act, Paycheck Protection Program
Receivable [Line Items]
Total loans	$ 36,013,000		48,656,000
Decrease due to forgiveness of loan	12,672,000
WebBank
Receivable [Line Items]
Servicing asset	1,901,000		$ 2,700,000
Proceeds from loans held for sale	4,275,373,000	$ 3,006,100,000
Allowance for loan loss increase	$ 7,003,000
Allowance for loan loss increase, percentage	23.60%