Debt and Equity Securities - Additional Information (Details)	9 Months Ended
	Sep. 30, 2023 USD ($) Security	Dec. 31, 2022 USD ($)
Investments, Debt and Equity Securities [Line Items]
Allowance for credit losses on available-for-sale securities	$ 0
Amortized Cost	918,905,000	$ 972,315,000
investment securities available-for-sale	755,779,000	822,812,000
Unrealized losses	163,173,000	149,504,000
Unrealized losses	750,385,000	822,246,000
Asset Pledged as Collateral | Public Deposits and Other Required Purposes
Investments, Debt and Equity Securities [Line Items]
Amortized Cost	485,873,000	477,051,000
investment securities available-for-sale	399,882,000	405,403,000
Collateralized Mortgage Obligations
Investments, Debt and Equity Securities [Line Items]
Amortized Cost	138,420,000	148,460,000
investment securities available-for-sale	113,130,000	126,190,000
U.S. Government Sponsored Entities and Agencies
Investments, Debt and Equity Securities [Line Items]
investment securities available-for-sale	9,000,000
Unrealized losses	$ 2,000,000
Percent of mortgage-backed securities	98.00%
Asset-Backed Securities
Investments, Debt and Equity Securities [Line Items]
Amortized Cost	$ 42,763,000	47,538,000
investment securities available-for-sale	41,006,000	45,250,000
Unrealized losses	1,803,000	2,288,000
Unrealized losses	35,994,000	45,250,000
Corporate Debt Security
Investments, Debt and Equity Securities [Line Items]
Amortized Cost	2,500,000	2,500,000
investment securities available-for-sale	2,403,000	2,403,000
Unrealized losses	97,000	97,000
Unrealized losses	$ 2,403,000	$ 2,403,000
Securities Other than U.S. Government and its Agencies
Investments, Debt and Equity Securities [Line Items]
Number of security holdings greater than 10% percent of shareholders' equity | Security	0