INVESTMENT SECURITIES - Allowance for Credit Losses (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Allowance for credit losses:
Beginning balance	$ 749	$ 701	$ 744	$ 704
Provision for (recovery of) credit losses	38	3	43	0
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Ending balance	787	704	787	704
Non-GSE commercial certificates
Allowance for credit losses:
Beginning balance	40	47	41	49
Provision for (recovery of) credit losses	(2)	0	(3)	(2)
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Ending balance	38	47	38	47
Commercial PACE
Allowance for credit losses:
Beginning balance	335	271	328	268
Provision for (recovery of) credit losses	31	7	38	10
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Ending balance	366	278	366	278
Residential PACE
Allowance for credit losses:
Beginning balance	374	383	375	387
Provision for (recovery of) credit losses	9	(4)	8	(8)
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Ending balance	$ 383	$ 379	$ 383	$ 379

Amount, excluding accrued interest, of allowance for credit loss on investment in debt security measured at amortized cost (held-to-maturity).

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 investment in debt security measured at amortized cost (held-to-maturity) from recovery.

+ 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

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

+ References

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- Definition

Amount, excluding accrued interest, of decrease in allowance for credit loss on investment in debt security measured at amortized cost (held-to-maturity) from writeoff.

+ References

Reference 1: 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 investment in debt security measured at amortized cost (held-to-maturity).

+ 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

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 22
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147476148/220-40-50-22

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