MERGERS AND ACQUISITIONS - Schedule of Estimated Acquisition-date Fair Values of the Assets Acquired and Liabilities Assumed (Details) - USD ($) $ in Thousands	Mar. 01, 2025	Feb. 28, 2025	Apr. 01, 2024	Sep. 30, 2025	Dec. 31, 2024
Consideration paid
Goodwill				$ 383,323	$ 333,695
CrossFirst
Assets acquired
Cash and cash equivalents	$ 385,808
Securities	725,622
Portfolio loans, net of ACL	6,023,063
Premises and equipment	69,673
Other intangible assets	81,783
Other assets	212,832
Total assets acquired	7,498,781
Liabilities assumed
Deposits	6,571,699
Short-term borrowings	11,148
Long-term borrowings	68,922
Subordinated notes, net of unamortized issuance costs	0
Junior subordinated debt owed to unconsolidated trusts	2,238
Other liabilities	85,347
Total liabilities assumed	6,739,354
Net assets acquired	759,427
Consideration paid
Cash	4
Total consideration paid	808,980	$ 6,000
Goodwill	49,553
CrossFirst | Common stock
Consideration paid
Common stock, Preferred stock and Replacement awards	795,227
CrossFirst | Preferred stock
Consideration paid
Common stock, Preferred stock and Replacement awards	7,750
CrossFirst | Replacement awards
Consideration paid
Common stock, Preferred stock and Replacement awards	$ 5,999
M&M
Assets acquired
Cash and cash equivalents			$ 33,577
Securities			8,086
Portfolio loans, net of ACL			417,230
Premises and equipment			2,045
Other intangible assets			6,346
Other assets			10,461
Total assets acquired			477,745
Liabilities assumed
Deposits			392,838
Short-term borrowings			35,932
Long-term borrowings			1,450
Subordinated notes, net of unamortized issuance costs			3,911
Junior subordinated debt owed to unconsolidated trusts			2,594
Other liabilities			7,342
Total liabilities assumed			444,067
Net assets acquired			33,678
Consideration paid
Cash			15,200
Total consideration paid			49,575
Goodwill			15,897
M&M | Common stock
Consideration paid
Common stock, Preferred stock and Replacement awards			34,375
M&M | Preferred stock
Consideration paid
Common stock, Preferred stock and Replacement awards			0
M&M | Replacement awards
Consideration paid
Common stock, Preferred stock and Replacement awards			$ 0