ACQUISITIONS PCI Loans Acquired (Details) $ in Thousands	Nov. 12, 2021 USD ($)
Business Acquisition [Line Items]
Contractual cash flows not expected to be collected	$ 16,540
Blue Hills Bancorp, Inc. [Member]
Business Acquisition [Line Items]
Contractually required principal and interest at acquisition	768,018
Contractual cash flows not expected to be collected	(16,540)
Basis in PCI loans at acquisition - estimated fair value	760,038
Financing Receivable, Purchased with Credit Deterioration, Discount (Premium)	$ 8,560