Loans and Allowance for Credit Losses on Loans - Schedule of Activity in Allowance for Credit Losses on Loans by Portfolio Segment (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Analysis of allowance for loan losses
Beginning balance	$ 21,993	$ 19,241	$ 19,241
Impact of CECL adoption		1,924
Provision for (reversal of) credit losses	193	(258)
Charge-offs	(68)	(116)	(864)
Recoveries	11	23
Ending balance	22,129	20,814	21,993
Commercial real estate
Analysis of allowance for loan losses
Beginning balance	7,915	6,951	6,951
Impact of CECL adoption		875
Provision for (reversal of) credit losses	129	(951)
Charge-offs	0	(91)	(686)
Recoveries	0	0
Ending balance	8,044	6,784	7,915
SBA—real estate
Analysis of allowance for loan losses
Beginning balance	1,657	1,607	1,607
Impact of CECL adoption		(238)
Provision for (reversal of) credit losses	1,202	(140)
Charge-offs	(66)	(11)	(46)
Recoveries	0	0
Ending balance	2,793	1,218	1,657
SBA—non-real estate
Analysis of allowance for loan losses
Beginning balance	147	207	207
Impact of CECL adoption		(142)
Provision for (reversal of) credit losses	71	(7)
Charge-offs	0	(14)	(35)
Recoveries	11	23
Ending balance	229	67	147
C&I
Analysis of allowance for loan losses
Beginning balance	1,215	1,643	1,643
Impact of CECL adoption		(320)
Provision for (reversal of) credit losses	448	(53)
Charge-offs	0	0	(97)
Recoveries	0	0
Ending balance	1,663	1,270	1,215
Home mortgage
Analysis of allowance for loan losses
Beginning balance	11,045	8,826	8,826
Impact of CECL adoption		1,753
Provision for (reversal of) credit losses	(1,652)	893
Charge-offs	(2)	0	0
Recoveries	0	0
Ending balance	9,391	11,472	11,045
Consumer
Analysis of allowance for loan losses
Beginning balance	14	7	7
Impact of CECL adoption		(4)
Provision for (reversal of) credit losses	(5)	0
Charge-offs	0	0	0
Recoveries	0	0
Ending balance	$ 9	$ 3	$ 14

Financing Receivable Excluding Accrued Interest Credit Loss Impact of CECL Adoption

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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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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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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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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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