Loans Receivable and Allowance for Credit Losses - Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Allowance for Loan and Lease Losses [Roll Forward]
Balance	$ 15,925	$ 10,310	$ 10,310
Charge-offs	(3,112)	(1,798)	(18,417)
Recoveries	311	180
Provisions (credits)	653	3,087
Balance	13,777	24,780	15,925
Impact of ASC 326 Adoption
Allowance for Loan and Lease Losses [Roll Forward]
Balance		13,001	13,001
Unfunded Loan Commitment
Allowance for Loan and Lease Losses [Roll Forward]
Provisions (credits)	5	(867)
Commercial Real Estate
Allowance for Loan and Lease Losses [Roll Forward]
Balance	6,089	6,966	6,966
Charge-offs	(158)	0	(6,346)
Recoveries	0	0
Provisions (credits)	(311)	1,217
Balance	5,620	9,809	6,089
Commercial Real Estate \| Impact of ASC 326 Adoption
Allowance for Loan and Lease Losses [Roll Forward]
Balance		1,626	1,626
Residential Real Estate
Allowance for Loan and Lease Losses [Roll Forward]
Balance	607	665	665
Charge-offs	(21)	0	(515)
Recoveries	0	0
Provisions (credits)	85	(1)
Balance	671	853	607
Residential Real Estate \| Impact of ASC 326 Adoption
Allowance for Loan and Lease Losses [Roll Forward]
Balance		189	189
Commercial and Industrial
Allowance for Loan and Lease Losses [Roll Forward]
Balance	1,269	1,403	1,403
Charge-offs	(410)	(2)	(927)
Recoveries	6	7
Provisions (credits)	334	172
Balance	1,199	1,799	1,269
Commercial and Industrial \| Impact of ASC 326 Adoption
Allowance for Loan and Lease Losses [Roll Forward]
Balance		219	219
Consumer and Other
Allowance for Loan and Lease Losses [Roll Forward]
Balance	7,843	1,207	1,207
Charge-offs	(2,523)	(1,796)	(10,479)
Recoveries	305	173
Provisions (credits)	655	1,690
Balance	6,280	12,251	7,843
Consumer and Other \| Impact of ASC 326 Adoption
Allowance for Loan and Lease Losses [Roll Forward]
Balance		10,977	10,977
Construction
Allowance for Loan and Lease Losses [Roll Forward]
Balance	4	24	24
Charge-offs	0	0	(150)
Recoveries	0	0
Provisions (credits)	3	1
Balance	7	21	4
Construction \| Impact of ASC 326 Adoption
Allowance for Loan and Lease Losses [Roll Forward]
Balance		(4)	(4)
Construction to Permanent - CRE
Allowance for Loan and Lease Losses [Roll Forward]
Balance	113	10	10
Charge-offs	0	0
Recoveries	0	0
Provisions (credits)	(113)	8
Balance	0	47	113
Construction to Permanent - CRE \| Impact of ASC 326 Adoption
Allowance for Loan and Lease Losses [Roll Forward]
Balance		29	29
Unallocated
Allowance for Loan and Lease Losses [Roll Forward]
Balance	0	35	35
Charge-offs	0	0
Recoveries	0	0
Provisions (credits)	0	0
Balance	$ 0	0	0
Unallocated \| Impact of ASC 326 Adoption
Allowance for Loan and Lease Losses [Roll Forward]
Balance		$ (35)	$ (35)

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- Definition

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

+ 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

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-13

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-6

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-13

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- Definition

Amount, excluding accrued interest, of credit loss expense (reversal of expense) on financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-13

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