LOANS AND ALLOWANCE FOR LOAN AND LEASE LOSSES (Narrative) (Details)	12 Months Ended			24 Months Ended	36 Months Ended
	Dec. 31, 2025 USD ($) segment	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2025 USD ($)	Dec. 31, 2025 USD ($)	Jun. 26, 2025 USD ($)	Apr. 01, 2025 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gain on CRE loan sale	$ 10,915,000	$ 0	$ 0
Nonaccrual loans, interest income	0	0	0
Loans under modified terms	45,424,000	35,177,000	51,237,000
Amortized Cost	45,424,000	35,177,000	51,237,000
Total Allowance for credit losses	$ 295,108,000	178,644,000	132,182,000	$ 295,108,000	$ 295,108,000
Number of reportable segments | segment	2
Loans held for investment, accrued interest receivable	$ 106,500,000	$ 73,700,000		106,500,000	106,500,000
Financing Receivable Accrued Interest After Allowance For Credit Loss Statement Of Financial Position Extensible List Not Disclosed (Flag)	true	true
Accrued interest receivable write-offs	$ 0	$ 0	0
Revolving loans converted to term				0
Sandy Spring
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid principle balance of CRE loans acquired						$ 2,000,000,000
Commercial Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Allowance for credit losses	232,813,000	148,887,000	105,896,000	232,813,000	232,813,000
CRE | Sandy Spring
Accounts, Notes, Loans and Financing Receivable [Line Items]
LHFS							$ 1,839,638,000
Gain on CRE loan sale	10,900,000
Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gain on CRE loan sale	10,900,000
Troubled Loan Modifications
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans under modified terms	0	0	0
Amortized Cost	$ 0	0	$ 0
Period for restructured loan to be considered default	90 days
Unfunded commitments on loans modified and designated as TLMs	$ 0	$ 0		$ 0	0
TLM loans that went into default					$ 0