REGULATORY CAPITAL MATTERS (Details) $ in Thousands	Dec. 31, 2025 USD ($)	Dec. 31, 2024 USD ($)
Total Capital (to risk-weighted assets)
Capital	$ 1,301,075	$ 1,294,263
Capital to Risk Weighted Assets (as a percent)	0.1573	0.1600
Capital Required for Capital Adequacy	$ 661,851	$ 647,103
Capital Required for Capital Adequacy to Risk Weighted Assets (as a percent)	0.0800	0.0800
Plus Capital Conservation Buffer	$ 868,679	$ 849,323
Plus Capital Conservation Buffer to Risk Weighted Assets (as a percent)	0.1050	0.1050
Common Equity Tier 1 Capital (to risk-weighted assets)
Common Equity Tier 1 Risk Based Capital	$ 1,173,283	$ 1,143,360
Common Equity Tier 1 Risk Based Capital to Risk Weighted Assets (as a percent)	14.18%	14.14%
Common Equity Tier 1 Risk Based Capital Required for Capital Adequacy	$ 372,291	$ 363,996
Common Equity Tier 1 Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets (as a percent)	4.50%	4.50%
Plus Common Equity Tier 1 Risk Based Capital	$ 579,119	$ 566,215
Plus Common Equity Tier 1 Risk Based Capital to Risk Weighted Assets (as a percent)	0.0700	0.0700
Tier 1 Capital (to risk-weighted assets)
Tier 1 Risk Based Capital	$ 1,183,509	$ 1,153,258
Tier 1 Risk Based Capital to Risk Weighted Assets (as a percent)	0.1431	0.1426
Tier 1 Risk Based Capital Required for Capital Adequacy	$ 496,388	$ 485,328
Tier 1 Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets (as a percent)	0.0600	0.0600
Plus Tier 1 Risk Based Capital	$ 703,216	$ 687,547
Plus Tier 1 Risk Based Capital to Risk Weighted Assets (as a percent)	0.0850	0.0850
Tier 1 Leverage (to average tangible assets)
Tier 1 Leverage	$ 1,183,509	$ 1,153,258
Tier 1 Leverage to Average Assets (as a percent)	0.1152	0.1131
Tier 1 Leverage Required for Capital Adequacy	$ 410,785	$ 407,750
Tier 1 Leverage Required for Capital Adequacy to Average Assets (as a percent)	0.0400	0.0400
Plus Tier 1 Leverage	$ 410,785	$ 407,750
Plus Tier 1 Leverage to Average Assets (as a percent)	0.0400	0.0400
Stellar Bank
Total Capital (to risk-weighted assets)
Capital	$ 1,241,007	$ 1,233,994
Capital to Risk Weighted Assets (as a percent)	0.1503	0.1528
Capital Required for Capital Adequacy	$ 660,452	$ 646,030
Capital Required for Capital Adequacy to Risk Weighted Assets (as a percent)	0.0800	0.0800
Plus Capital Conservation Buffer	$ 866,844	$ 847,915
Plus Capital Conservation Buffer to Risk Weighted Assets (as a percent)	0.1050	0.1050
Capital Required to be Well Capitalized	$ 825,566	$ 807,538
Capital Required to be Well Capitalized to Risk Weighted Assets (as a percent)	0.1000	0.1000
Common Equity Tier 1 Capital (to risk-weighted assets)
Common Equity Tier 1 Risk Based Capital	$ 1,141,442	$ 1,140,989
Common Equity Tier 1 Risk Based Capital to Risk Weighted Assets (as a percent)	13.83%	14.13%
Common Equity Tier 1 Risk Based Capital Required for Capital Adequacy	$ 371,504	$ 363,392
Common Equity Tier 1 Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets (as a percent)	4.50%	4.50%
Plus Common Equity Tier 1 Risk Based Capital	$ 577,896	$ 565,277
Plus Common Equity Tier 1 Risk Based Capital to Risk Weighted Assets (as a percent)	0.0700	0.0700
Common Equity Tier 1 Risk Based Capital Required to be Well Capitalized	$ 536,618	$ 524,900
Common Equity Tier 1 Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets (as a percent)	6.50%	6.50%
Tier 1 Capital (to risk-weighted assets)
Tier 1 Risk Based Capital	$ 1,141,442	$ 1,140,989
Tier 1 Risk Based Capital to Risk Weighted Assets (as a percent)	0.1383	0.1413
Tier 1 Risk Based Capital Required for Capital Adequacy	$ 495,339	$ 484,523
Tier 1 Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets (as a percent)	0.0600	0.0600
Plus Tier 1 Risk Based Capital	$ 701,731	$ 686,407
Plus Tier 1 Risk Based Capital to Risk Weighted Assets (as a percent)	0.0850	0.0850
Tier 1 Risk Based Capital Required to be Well Capitalized	$ 660,452	$ 646,030
Plus Tier 1 Risk Based Capital to Risk Weighted Assets (as a percent)	0.0800	0.0800
Tier 1 Leverage (to average tangible assets)
Tier 1 Leverage	$ 1,141,442	$ 1,140,989
Tier 1 Leverage to Average Assets (as a percent)	0.1114	0.1121
Tier 1 Leverage Required for Capital Adequacy	$ 410,038	$ 407,219
Tier 1 Leverage Required for Capital Adequacy to Average Assets (as a percent)	0.0400	0.0400
Plus Tier 1 Leverage	$ 410,038	$ 407,219
Plus Tier 1 Leverage to Average Assets (as a percent)	0.0400	0.0400
Tier 1 Leverage Required to be Well Capitalized	$ 512,548	$ 509,024
Tier 1 Leverage Required to be Well Capitalized to Average Assets (as a percent)	0.0500	0.0500

Common equity tier1 capital.

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Tier I Capital.

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Tier I capital.

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Total capital.

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Amount of total capital as defined by regulatory framework.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 505
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477270/942-505-50-1

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-Topic 942
-SubTopic 505
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477270/942-505-50-1B

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