LOANS RECEIVABLE, NET - Schedule of Activity in Allowance by Portfolio (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025
Allowance for credit losses:
Beginning balance	$ 68,155	$ 57,676	$ 57,586	$ 60,086	$ 60,086
Provision for (recovery of) credit losses	3,944	4,774	17,779	4,940
Charge-offs	(3,683)	(4,038)	(7,432)	(7,015)	(23,452)
Recoveries	523	586	1,006	987
Ending balance	68,939	58,998	68,939	58,998	57,586
Commercial portfolio \| Commercial and industrial
Allowance for credit losses:
Beginning balance	11,279	15,322	13,276	13,505	13,505
Provision for (recovery of) credit losses	660	2,631	(513)	5,261
Charge-offs	(215)	(1,148)	(1,074)	(1,971)	(10,366)
Recoveries	13	214	48	224
Ending balance	11,737	17,019	11,737	17,019	13,276
Commercial portfolio \| Multifamily
Allowance for credit losses:
Beginning balance	16,872	3,151	4,792	2,794	2,794
Provision for (recovery of) credit losses	956	(394)	13,109	(37)
Charge-offs	(4)	0	(77)	0	(2,471)
Recoveries	0	0	0	0
Ending balance	17,824	2,757	17,824	2,757	4,792
Commercial portfolio \| Commercial real estate
Allowance for credit losses:
Beginning balance	1,697	1,589	1,779	1,600	1,600
Provision for (recovery of) credit losses	226	498	144	487
Charge-offs	0	0	0	0	0
Recoveries	0	0	0	0
Ending balance	1,923	2,087	1,923	2,087	1,779
Commercial portfolio \| Construction and land development
Allowance for credit losses:
Beginning balance	1,463	1,252	1,506	1,253	1,253
Provision for (recovery of) credit losses	(1,451)	34	(1,494)	33
Charge-offs	0	0	0	0	0
Recoveries	0	0	0	0
Ending balance	12	1,286	12	1,286	1,506
Retail portfolio \| Residential real estate lending
Allowance for credit losses:
Beginning balance	7,012	9,538	7,157	9,493	9,493
Provision for (recovery of) credit losses	(258)	(601)	(519)	(562)
Charge-offs	0	(235)	(2)	(304)	(304)
Recoveries	55	274	173	349
Ending balance	6,809	8,976	6,809	8,976	7,157
Retail portfolio \| Consumer solar
Allowance for credit losses:
Beginning balance	28,961	25,005	28,149	29,095	29,095
Provision for (recovery of) credit losses	3,868	2,620	7,106	238
Charge-offs	(3,453)	(2,643)	(6,192)	(4,617)	(10,140)
Recoveries	450	92	763	358
Ending balance	29,826	25,074	29,826	25,074	28,149
Retail portfolio \| Consumer and Other
Allowance for credit losses:
Beginning balance	871	1,819	927	2,346	2,346
Provision for (recovery of) credit losses	(57)	(14)	(54)	(480)
Charge-offs	(11)	(12)	(87)	(123)	(171)
Recoveries	5	6	22	56
Ending balance	$ 808	$ 1,799	$ 808	$ 1,799	$ 927

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477657/942-210-S45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478478/942-210-S50-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(7)(2))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479344/326-20-45-1

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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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

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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-Section 50
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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