Summary of Significant Accounting Policies - Summary of Allowance of Credit Losses (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Jan. 01, 2023	Dec. 31, 2022	Dec. 31, 2021
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Allowance for credit loss	$ 21,183	$ 20,906	$ 20,628	$ 19,176
Unfunded commitments
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Allowance for credit loss	442	442	0
Real estate | Commercial real estate
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Allowance for credit loss	8,649	8,596	7,720	6,749
Real estate | One-to-four family residential
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Allowance for credit loss	7,475	6,913	5,682	5,375
Real estate | Construction and development
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Allowance for credit loss	1,233	1,210	1,654	1,326
Commercial and industrial
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Allowance for credit loss	2,940	3,528	4,350	4,440
SBA PPP, net of deferred income
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Allowance for credit loss	0	0	0	25
Tax-exempt
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Allowance for credit loss	579	324	751	749
Consumer
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Allowance for credit loss	$ 307	$ 335	471	$ 512
Impact of ASC 326 Adoption
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Allowance for credit loss			278
Impact of ASC 326 Adoption | Unfunded commitments
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Allowance for credit loss			442
Impact of ASC 326 Adoption | Real estate | Commercial real estate
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Allowance for credit loss			876
Impact of ASC 326 Adoption | Real estate | One-to-four family residential
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Allowance for credit loss			1,231
Impact of ASC 326 Adoption | Real estate | Construction and development
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Allowance for credit loss			(444)
Impact of ASC 326 Adoption | Commercial and industrial
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Allowance for credit loss			(822)
Impact of ASC 326 Adoption | SBA PPP, net of deferred income
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Allowance for credit loss			0
Impact of ASC 326 Adoption | Tax-exempt
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Allowance for credit loss			(427)
Impact of ASC 326 Adoption | Consumer
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Allowance for credit loss			$ (136)