SEGMENT INFORMATION - Segment income (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
INTEREST INCOME
Total interest income	$ 3,966	$ 3,595	$ 7,794	$ 7,032
INTEREST EXPENSE
Total interest expense	1,358	1,364	2,742	2,673
Net interest income	2,608	2,231	5,052	4,359
Provision for credit losses available-for-sale securities	148		148
(Benefit) provision for credit losses loans receivable	(28)	511	92	621
Net interest income after provision for credit losses	2,488	1,720	4,812	3,738
NONINTEREST INCOME
Gain on sale of fixed assets			6
Earnings on deferred compensation plan assets	35	26	68	52
Net gains on sale of residential mortgage loans	25	32	49	65
Total noninterest income	626	531	1,230	1,017
NONINTEREST EXPENSE
Compensation and employee benefits	1,571	1,387	3,150	2,673
Core processing	479	376	942	711
Premises and equipment	261	222	571	445
Professional fees	249	106	423	163
Postage and office supplies	25	15	49	58
FDIC premiums	59	34	114	67
Advertising	64	85	156	183
Director fees	55	37	101	85
Intangible asset amortization	39	40	78	79
Other	233	180	422	345
Total noninterest expense	3,035	2,482	6,006	4,809
Income (Loss) before benefit for income taxes	79	(231)	36	(54)
BENEFIT FOR INCOME TAXES	(14)	(35)	(7)	(6)
Net income (loss)	93	(196)	43	(48)
Service fees
NONINTEREST INCOME
Non-interest income	39	33	74	65
Income from financial services
NONINTEREST INCOME
Non-interest income	245	240	507	464
Fee income
NONINTEREST INCOME
Non-interest income	282	200	526	371
Operating Segments | Seneca Savings
INTEREST INCOME
Total interest income	3,966	3,595	7,794	7,032
INTEREST EXPENSE
Total interest expense	1,358	1,364	2,742	2,673
Net interest income	2,608	2,231	5,052	4,359
Provision for credit losses available-for-sale securities	148		148
(Benefit) provision for credit losses loans receivable	(28)	511	92	621
Net interest income after provision for credit losses	2,488	1,720	4,812	3,738
NONINTEREST INCOME
Gain on sale of fixed assets			6
Earnings on deferred compensation plan assets	35	26	68	52
Net gains on sale of residential mortgage loans	25	32	49	65
Total noninterest income	373	283	707	537
NONINTEREST EXPENSE
Compensation and employee benefits	1,431	1,268	2,870	2,438
Core processing	479	376	942	711
Premises and equipment	255	216	559	433
Professional fees	244	106	403	163
Postage and office supplies	24	14	48	57
FDIC premiums	59	34	114	67
Advertising	63	82	154	179
Director fees	54	37	100	84
Intangible asset amortization				1
Other	223	167	395	321
Total noninterest expense	2,832	2,300	5,585	4,454
Income (Loss) before benefit for income taxes	29	(297)	(66)	(179)
BENEFIT FOR INCOME TAXES	(14)	(35)	(7)	(6)
Net income (loss)	43	(262)	(59)	(173)
Operating Segments | Seneca Savings | Service fees
NONINTEREST INCOME
Non-interest income	39	33	74	65
Operating Segments | Seneca Savings | Fee income
NONINTEREST INCOME
Non-interest income	274	192	510	355
Operating Segments | Financial Quest
NONINTEREST INCOME
Total noninterest income	253	248	523	480
NONINTEREST EXPENSE
Compensation and employee benefits	140	119	280	235
Premises and equipment	6	6	12	12
Professional fees	5		20
Postage and office supplies	1	1	1	1
Advertising	1	3	2	4
Director fees	1		1	1
Intangible asset amortization	39	40	78	78
Other	10	13	27	24
Total noninterest expense	203	182	421	355
Income (Loss) before benefit for income taxes	50	66	102	125
Net income (loss)	50	66	102	125
Operating Segments | Financial Quest | Income from financial services
NONINTEREST INCOME
Non-interest income	245	240	507	464
Operating Segments | Financial Quest | Fee income
NONINTEREST INCOME
Non-interest income	$ 8	$ 8	$ 16	$ 16