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
Mar. 31, 2023	Mar. 31, 2022
Analysis of allowance for loan losses
Beginning balance	$ 19,241	$ 16,123
Impact of CECL adoption	1,924
(Reversal of) provision for credit losses	(258)	546
Charge-offs	(116)	(14)
Recoveries	23	17
Ending balance	20,814	16,672
(Reversal of) provision for credit losses	(338)	341
Uncollectible Accrued Interest Receivable
Analysis of allowance for loan losses
(Reversal of) provision for credit losses		(205)
Commercial Real Estate
Analysis of allowance for loan losses
Beginning balance	6,951	8,150
Impact of CECL adoption	875
(Reversal of) provision for credit losses	(951)	(1,670)
Charge-offs	(91)	0
Recoveries	0	0
Ending balance	6,784	6,480
SBA—real estate
Analysis of allowance for loan losses
Beginning balance	1,607	2,022
Impact of CECL adoption	(238)
(Reversal of) provision for credit losses	(140)	(258)
Charge-offs	(11)	(14)
Recoveries	0	0
Ending balance	1,218	1,750
SBA—non-real estate
Analysis of allowance for loan losses
Beginning balance	207	199
Impact of CECL adoption	(142)
(Reversal of) provision for credit losses	(7)	(47)
Charge-offs	(14)	0
Recoveries	23	17
Ending balance	67	169
C&I
Analysis of allowance for loan losses
Beginning balance	1,643	2,848
Impact of CECL adoption	(320)
(Reversal of) provision for credit losses	(53)	644
Charge-offs	0	0
Recoveries	0	0
Ending balance	1,270	3,492
Home mortgage
Analysis of allowance for loan losses
Beginning balance	8,826	2,891
Impact of CECL adoption	1,753
(Reversal of) provision for credit losses	893	1,877
Charge-offs	0	0
Recoveries	0	0
Ending balance	11,472	4,768
Consumer
Analysis of allowance for loan losses
Beginning balance	7	13
Impact of CECL adoption	(4)
(Reversal of) provision for credit losses	0	0
Charge-offs	0	0
Recoveries	0	0
Ending balance	$ 3	$ 13

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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=124255206&loc=SL82895884-210446

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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.

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (e)
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (d)
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

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- Definition

Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(2)
-URI https://asc.fasb.org/extlink&oid=123577603&loc=SL6953423-111524

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
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-URI https://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260

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-SubTopic 10
-Section 45
-Paragraph 28
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-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3602-108585

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