Loans and Allowance for Credit Losses - Loans - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2023	Dec. 31, 2022
Financing Receivable, Allowance for Credit Losses [Line Items]
Deferred fees and costs	$ 4,200	$ 3,900	$ 4,200	$ 3,900
Accrued interest	$ 22,100		$ 22,100
Financing Receivable, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration]	Other assets		Other assets
Loans to certain executive officers, directors, and their related interests	$ 22,000	30,700	$ 22,000	30,700
Loans to certain executive officers, directors, and their related interests, new loans and advances			5,500
Loans to certain executive officers, directors, and their related interests, repayments			3,600
Loans and leases receivable, not extended to related parties	10,800		10,800
Nonaccrual, interest income	174	124	1,200	729
Foreclosure proceedings in process	121	122	121	122
Financing receivable, net	4,218,605	3,495,162	$ 4,218,605	3,495,162
Weighted average term increase from modification			2 years
PPP Loans | Small Business Administration
Financing Receivable, Allowance for Credit Losses [Line Items]
Financing receivable, net	$ 1,400	$ 2,600	$ 1,400	$ 2,600