Fair Value of Assets and Liabilities - Additional Information (Details) - USD ($)	3 Months Ended		12 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023	Dec. 31, 2022
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Allowance for Credit Losses	$ 308,000
Other real estate owned	1,346,000		$ 1,163,000
Mortgage Servicing Rights
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Finite-lived intangible assets, net	6,459,000	$ 312,000	6,859,000	$ 331,000
Mortgage servicing rights (MSR) impairment (recovery)	(33,000)	$ 0	$ (8,000)
Fair Value, Nonrecurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Carrying amount of loans with a specific allowance	1,300,000
Fair value of loans with a specific allowance	1,000,000
Allowance for Credit Losses	324,000
Fair Value, Nonrecurring | Carrying Amount
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Other real estate owned	1,300,000
Fair Value, Nonrecurring | Fair Value
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Other real estate owned	$ 0