FAIR VALUE MEASUREMENTS - Schedule of Activity for Financial Assets Measured at Fair Value on a Recurring Basis (Details) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2025 USD ($)	Jun. 30, 2024 USD ($)	Jun. 30, 2025 USD ($) agreement	Jun. 30, 2024 USD ($)
CrossFirst
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Number of risk participation agreements amended \| agreement			1
Risk participation agreement, new sales previously recorded as reduction to losses recognized in earnings			$ 6
Fair Value, Recurring \| Level 3 Inputs
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair value, beginning balance	$ (39)	$ 9	5	$ 15
Gains (losses) recognized in earnings	2	(1)	(7)	(10)
Purchases	(26)	0	(26)	3
Sales	18	0	24	0
Assumed in acquisition	0	0	(41)	0
Fair value, ending balance	$ (45)	$ 8	$ (45)	$ 8
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Other noninterest expense	Other noninterest expense	Other noninterest expense	Other noninterest expense

Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Assumed In Acquisition

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- Definition

Number Of Risk Participation Agreements Amended

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- Definition

Risk Participation Agreement, New Sales Previously Recorded As Reduction To Losses Recognized In Earnings

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

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- Definition

Amount of gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3).

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- Definition

Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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- Definition

Amount of sale of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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- Definition

Indicates line item in statement of income or comprehensive income that includes gain (loss) from asset measured at fair value using unobservable input (level 3).

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