LOANS AND ALLOWANCE FOR CREDIT LOSSES - Loans By Credit Quality Indicators and Origination Year (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2026	Dec. 31, 2025
LOANS
Year I	$ 94,052	$ 292,181
Year II	280,561	228,286
Year III	223,023	310,656
Year IV	297,841	386,711
Year V	370,522	250,475
Prior	866,986	647,579
Revolving	251,865	238,477
Total	2,384,850	2,354,365
Current period gross charge-offs
Year I	0	0
Year II	0	0
Year III	6	33
Year IV	3	40
Year V	10,248	336
Prior	471	812
Revolving	105	505
Total	10,833	1,726
Pass
LOANS
Year I	94,052	290,253
Year II	276,674	214,314
Year III	208,983	304,177
Year IV	293,938	357,047
Year V	351,603	231,872
Prior	806,667	607,210
Revolving	243,141	232,380
Total	2,275,058	2,237,253
Special Mention
LOANS
Year I	0	1,457
Year II	3,414	909
Year III	827	4,380
Year IV	1,690	17,179
Year V	194	7,321
Prior	24,595	13,904
Revolving	4,020	2,028
Total	34,740	47,178
Substandard
LOANS
Year I	0	471
Year II	473	13,063
Year III	13,213	2,099
Year IV	2,213	12,485
Year V	18,725	11,282
Prior	35,724	26,465
Revolving	4,704	4,069
Total	75,052	69,934
Doubtful
LOANS
Year I	0	0
Year II	0	0
Year III	0	0
Year IV	0	0
Year V	0	0
Prior	0	0
Revolving	0	0
Total	0	0
Commercial \| Commercial real estate - non-owner occupied
LOANS
Year I	31,510	82,909
Year II	75,814	84,462
Year III	83,780	152,500
Year IV	155,239	197,798
Year V	185,286	94,473
Prior	394,252	315,596
Revolving	0	0
Total	925,881	927,738
Current period gross charge-offs
Year I	0	0
Year II	0	0
Year III	0	0
Year IV	0	0
Year V	10,196	0
Prior	256	807
Revolving	0	0
Total	10,452	807
Commercial \| Commercial real estate - non-owner occupied \| Pass
LOANS
Year I	31,510	82,832
Year II	75,489	84,330
Year III	83,651	149,720
Year IV	153,039	171,419
Year V	169,174	90,420
Prior	369,499	295,369
Revolving	0	0
Total	882,362	874,090
Commercial \| Commercial real estate - non-owner occupied \| Special Mention
LOANS
Year I	0	77
Year II	325	30
Year III	30	1,942
Year IV	1,388	15,920
Year V	0	2,073
Prior	12,717	8,045
Revolving	0	0
Total	14,460	28,087
Commercial \| Commercial real estate - non-owner occupied \| Substandard
LOANS
Year I	0	0
Year II	0	102
Year III	99	838
Year IV	812	10,459
Year V	16,112	1,980
Prior	12,036	12,182
Revolving	0	0
Total	29,059	25,561
Commercial \| Commercial real estate - non-owner occupied \| Doubtful
LOANS
Year I	0	0
Year II	0	0
Year III	0	0
Year IV	0	0
Year V	0	0
Prior	0	0
Revolving	0	0
Total	0	0
Commercial \| Commercial real estate - owner occupied
LOANS
Year I	21,451	34,602
Year II	34,336	37,143
Year III	36,751	38,171
Year IV	37,454	54,550
Year V	53,519	54,368
Prior	142,699	92,958
Revolving	0	0
Total	326,210	311,792
Current period gross charge-offs
Year I	0	0
Year II	0	0
Year III	0	0
Year IV	0	0
Year V	0	0
Prior	0	0
Revolving	0	0
Total	0	0
Commercial \| Commercial real estate - owner occupied \| Pass
LOANS
Year I	21,451	34,602
Year II	34,336	36,786
Year III	36,397	35,411
Year IV	36,727	53,260
Year V	52,569	51,396
Prior	127,719	80,809
Revolving	0	0
Total	309,199	292,264
Commercial \| Commercial real estate - owner occupied \| Special Mention
LOANS
Year I	0	0
Year II	0	357
Year III	354	2,406
Year IV	272	1,159
Year V	110	805
Prior	5,877	5,127
Revolving	0	0
Total	6,613	9,854
Commercial \| Commercial real estate - owner occupied \| Substandard
LOANS
Year I	0	0
Year II	0	0
Year III	0	354
Year IV	455	131
Year V	840	2,167
Prior	9,103	7,022
Revolving	0	0
Total	10,398	9,674
Commercial \| Commercial real estate - owner occupied \| Doubtful
LOANS
Year I	0	0
Year II	0	0
Year III	0	0
Year IV	0	0
Year V	0	0
Prior	0	0
Revolving	0	0
Total	0	0
Commercial \| All other commercial loans
LOANS
Year I	28,396	125,384
Year II	120,019	58,602
Year III	56,224	64,135
Year IV	51,048	48,241
Year V	46,885	55,432
Prior	121,222	69,019
Revolving	148,122	139,724
Total	571,916	560,537
Current period gross charge-offs
Year I	0	0
Year II	0	0
Year III	0	0
Year IV	0	0
Year V	52	333
Prior	215	0
Revolving	0	263
Total	267	596
Commercial \| All other commercial loans \| Pass
LOANS
Year I	28,396	123,534
Year II	116,460	45,148
Year III	42,706	64,103
Year IV	51,018	46,670
Year V	45,422	44,056
Prior	104,821	64,539
Revolving	140,232	134,404
Total	529,055	522,454
Commercial \| All other commercial loans \| Special Mention
LOANS
Year I	0	1,380
Year II	3,089	522
Year III	443	32
Year IV	30	100
Year V	84	4,443
Prior	6,001	732
Revolving	4,020	2,028
Total	13,667	9,237
Commercial \| All other commercial loans \| Substandard
LOANS
Year I	0	470
Year II	470	12,932
Year III	13,075	0
Year IV	0	1,471
Year V	1,379	6,933
Prior	10,400	3,748
Revolving	3,870	3,292
Total	29,194	28,846
Commercial \| All other commercial loans \| Doubtful
LOANS
Year I	0	0
Year II	0	0
Year III	0	0
Year IV	0	0
Year V	0	0
Prior	0	0
Revolving	0	0
Total	0	0
Residential mortgage
LOANS
Year I	11,604	46,534
Year II	48,057	46,010
Year III	44,518	54,064
Year IV	52,603	84,272
Year V	83,170	45,694
Prior	205,959	167,376
Revolving	0	0
Total	445,911	443,950
Current period gross charge-offs
Year I	0	0
Year II	0	0
Year III	0	0
Year IV	0	0
Year V	0	0
Prior	0	5
Revolving	0	0
Total	0	5
Residential mortgage \| Pass
LOANS
Year I	11,604	46,534
Year II	48,057	45,988
Year III	44,482	53,163
Year IV	51,680	83,848
Year V	82,776	45,494
Prior	201,925	164,033
Revolving	0	0
Total	440,524	439,060
Residential mortgage \| Special Mention
LOANS
Year I	0	0
Year II	0	0
Year III	0	0
Year IV	0	0
Year V	0	0
Prior	0	0
Revolving	0	0
Total	0	0
Residential mortgage \| Substandard
LOANS
Year I	0	0
Year II	0	22
Year III	36	901
Year IV	923	424
Year V	394	200
Prior	4,034	3,343
Revolving	0	0
Total	5,387	4,890
Residential mortgage \| Doubtful
LOANS
Year I	0	0
Year II	0	0
Year III	0	0
Year IV	0	0
Year V	0	0
Prior	0	0
Revolving	0
Total	0
Current period gross charge-offs
Revolving		0
Total		0
Consumer
LOANS
Year I	1,091	2,752
Year II	2,335	2,069
Year III	1,750	1,786
Year IV	1,497	1,850
Year V	1,662	508
Prior	2,854	2,630
Revolving	103,743	98,753
Total	114,932	110,348
Current period gross charge-offs
Year I	0	0
Year II	0	0
Year III	6	33
Year IV	3	40
Year V	0	3
Prior	0	0
Revolving	105	242
Total	114	318
Consumer \| Pass
LOANS
Year I	1,091	2,751
Year II	2,332	2,062
Year III	1,747	1,780
Year IV	1,474	1,850
Year V	1,662	506
Prior	2,703	2,460
Revolving	102,909	97,976
Total	113,918	109,385
Consumer \| Special Mention
LOANS
Year I	0	0
Year II	0	0
Year III	0	0
Year IV	0	0
Year V	0	0
Prior	0	0
Revolving	0	0
Total	0	0
Consumer \| Substandard
LOANS
Year I	0	1
Year II	3	7
Year III	3	6
Year IV	23	0
Year V	0	2
Prior	151	170
Revolving	834	777
Total	1,014	963
Consumer \| Doubtful
LOANS
Year I	0	0
Year II	0	0
Year III	0	0
Year IV	0	0
Year V	0	0
Prior	0	0
Revolving	0	0
Total	$ 0	$ 0

CITIZENS & NORTHERN CORP 10-Q