LOANS - Allowance for credit losses (Details) - USD ($)	3 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2024
LOANS
Balance, beginning	$ 438,595	$ 370,427	$ 438,595	$ 370,427	$ 435,675	$ 436,986	$ 354,659	$ 351,837
Provision for credit losses		12,940		12,940
Recoveries	1,609	2,828	2,920	5,650
Balance, ending	438,595	370,427	438,595	370,427	435,675
Single family
LOANS
Balance, beginning	239,627	200,761	239,627	200,761	224,121	232,710	226,194	226,570
Provision for credit losses	5,308	(28,261)	12,586	(31,459)
Recoveries	1,609	2,828	2,920	5,650
Balance, ending	239,627	200,761	239,627	200,761	224,121
Multifamily and nonresidential
LOANS
Balance, beginning	100,505	78,290	100,505	78,290	98,523	102,474	81,139	83,899
Provision for credit losses	(1,969)	(2,849)	1,982	(5,609)
Balance, ending	100,505	78,290	100,505	78,290	98,523
Construction and land
LOANS
Balance, beginning	12,176	6,441	12,176	6,441	12,199	10,230	6,050	4,017
Provision for credit losses	1,946	391	(23)	2,424
Balance, ending	12,176	6,441	12,176	6,441	12,199
Second mortgage
LOANS
Balance, beginning	437	412	437	412	506	446	534	268
Provision for credit losses	(9)	(122)	(69)	144
Balance, ending	437	412	437	412	506
Commercial
LOANS
Balance, beginning	14,978	18,462	14,978	18,462	20,185	18,957	26,865	25,665
Provision for credit losses	(3,979)	(8,403)	(5,207)	(7,203)
Charge offs					(7,657,780)
Balance, ending	14,978	18,462	14,978	18,462	20,185
Consumer
LOANS
Balance, beginning	70,872	66,061	70,872	66,061	80,141	$ 72,169	$ 13,877	$ 11,418
Provision for credit losses	(1,297)	52,184	(9,269)	54,643
Balance, ending	$ 70,872	$ 66,061	$ 70,872	$ 66,061	$ 80,141

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
-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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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 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
-Topic 326
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-Section 50
-Paragraph 6
-Publisher FASB
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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

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
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