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PORTFOLIO LOANS - Narrative (Details)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2025 USD ($) loan	Jun. 30, 2024 USD ($)	Jun. 30, 2025 USD ($)	Jun. 30, 2024 USD ($)	Dec. 31, 2024 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Net deferred loan origination costs	$ 10,800,000		$ 10,800,000		$ 12,500,000
Net accretable purchase accounting adjustments			(98,100,000)		(8,800,000)
Amount of interest collected and recognized on a cash basis	0	$ 0	0	$ 0
Collateral dependent loans secured by real estate or business assets	50,000,000		50,000,000		$ 19,300,000
Loans in the process of foreclosure	5,700,000		5,700,000
CrossFirst
Accounts, Notes, Loans and Financing Receivable [Line Items]
PCD loans acquired and fully reserved at acquisition			31,100,000
90+ Days
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross interest income that would have been recorded if impaired loans had been current	1,000,000	200,000	1,200,000	500,000
Retail loans | CRE
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans purchased	$ 0	$ 6,900,000	0	$ 6,900,000
Commercial loans | Watch
Accounts, Notes, Loans and Financing Receivable [Line Items]
Limit above which loans are annually reviewed			2,000,000
Commercial loans | Special Mention
Accounts, Notes, Loans and Financing Receivable [Line Items]
Limit above which loans are annually reviewed			350,000
Commercial loans | Maximum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Limit where loans are processed through an expedited underwriting process			2,000,000
Commercial loans | C&I and other commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of loans with default after modification | loan	1
Financing receivable with default after modification	$ 500,000		$ 500,000

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