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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 |  |  |

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- Definition Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 926 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Publisher FASB -URI https://asc.fasb.org//1943274/2147483154/926-20-50-5 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 350 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (a)(1) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482665/350-30-50-2 + Details
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- Definition The adjustment to the carrying value of the rights retained or purchased to service mortgages. These adjustments are made when the estimate of the fair value is changed. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 230 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 28 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482740/230-10-45-28 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Subparagraph (a)(6) -SubTopic 50 -Topic 860 -Publisher FASB -URI https://asc.fasb.org//1943274/2147481229/860-50-50-4 + Details
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