FAIR VALUE OF FINANCIAL INSTRUMENTS - Fair value option and gains and losses from fair value changes (Details) - Residential loans held for sale - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025
Fair Value, Option, Quantitative Disclosures [Line Items]
Aggregate fair value	$ 4,839		$ 7,781
Difference	116		390
Contractual principal	4,723		$ 7,391
Gains and losses from fair value changes
Residential loans held for sale	$ (238)	$ 87

Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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-Topic 820
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-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

+ Details

Midland States Bancorp, Inc. 10-Q