SALE OF COMMERCIAL REAL ESTATE BUSINESS - Narrative (Details) - USD ($) $ in Thousands		3 Months Ended
Mar. 25, 2021	Mar. 31, 2021	Mar. 31, 2020
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Business divestiture-related gains (losses)		$ (249,563)	$ 0
CRE Business \| Discontinued Operations, Disposed of by Sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Sale of business	$ 2,330,000
Goodwill, Impairment Loss	71,800
Business divestiture-related gains (losses)		(249,600)
Reversal of loan loss provision		135,000
Unfunded commitments	$ 5,100
Pretax loss		$ (72,700)	$ (95,400)

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