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LOANS AND ALLOWANCE FOR LOAN AND LEASE LOSSES (Schedule of Loans Acquired) (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
	Apr. 01, 2025	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
American National
Financing Receivable, Allowance for Credit Loss [Line Items]
Initial ACL at acquisition			$ (3,896)		$ (3,896)
Sandy Spring
Financing Receivable, Allowance for Credit Loss [Line Items]
Initial ACL at acquisition		$ (28,265)		$ (28,265)
Sandy Spring \| PCD
Financing Receivable, Allowance for Credit Loss [Line Items]
Book value of acquired loans at acquisition	$ 1,741,713
Initial ACL at acquisition	(28,265)
Non-credit discount at acquisition	(162,140)
Purchase Price	1,551,308
Sandy Spring \| Non-PCD
Financing Receivable, Allowance for Credit Loss [Line Items]
Fair Value	7,077,565
Gross contractual amounts receivable	10,502,561
Estimate of contractual cash flows not expected to be collected	$ 130,113