Loans - Narrative (Details) - USD ($)	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 7,049,746,000		$ 6,857,194,000
Syndication facilities included in loans	410,000,000		367,000,000
Collateral of cash, cash equivalents or other financial instruments	6,900,000		6,300,000
Interest income on nonaccrual loans	0	$ 0
Interest receivable	30,100,000		27,700,000
Reversal of interest receivable	200,000	200,000
International
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	96,200,000		99,200,000
Consumer loans and overdrafts
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	550,405,000		604,460,000
Reversal of interest receivable		100,000
Real estate loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	4,988,380,000		4,858,208,000
Reversal of interest receivable		100,000
Real estate loans | Single-family residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	1,189,045,000		1,102,845,000
Payments to acquire loans held-for-investment	1,000,000	0
Commercial loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	1,497,649,000		1,381,234,000
Commercial loans | Indirect Consumer Loans Purchased
Accounts, Notes, Loans and Financing Receivable [Line Items]
Payments to acquire loans held-for-investment	0	$ 124,000,000
Indirect Consumer Loans Purchased | Consumer loans and overdrafts
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	372,200,000		433,300,000
Pledged as Collateral
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 1,300,000,000		$ 1,200,000,000