Loans and the Allowance for Loan Losses - Loans Receivable (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing receivable, excluding accrued interest, before allowance for credit loss	$ 5,088,839	$ 4,992,785
Allowance for Loan Losses	(41,165)	(40,414)	$ (38,178)
Net Loans	5,047,674	4,952,371
Real Estate Loans:
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing receivable, excluding accrued interest, before allowance for credit loss	3,594,909	3,570,120
Real Estate Loans: \| Commercial
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing receivable, excluding accrued interest, before allowance for credit loss	2,215,889	2,217,928
Allowance for Loan Losses	(17,780)	(17,676)	(14,702)
Real Estate Loans: \| Construction
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing receivable, excluding accrued interest, before allowance for credit loss	662,013	669,798
Allowance for Loan Losses	(6,489)	(6,596)	(5,768)
Real Estate Loans: \| Residential
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing receivable, excluding accrued interest, before allowance for credit loss	717,007	682,394
Allowance for Loan Losses	(6,033)	(5,485)	(5,354)
Commercial
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing receivable, excluding accrued interest, before allowance for credit loss	1,426,957	1,358,838
Allowance for Loan Losses	(10,367)	(10,424)	(11,721)
Consumer and Other
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing receivable, excluding accrued interest, before allowance for credit loss	66,973	63,827
Allowance for Loan Losses	$ (496)	$ (233)	$ (633)

Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

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+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph c
-Publisher SEC

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+ References

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+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479344/326-20-45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3B
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-3B

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-5

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