ACQUISITIONS - Schedule of Fair Value and Unpaid Principal Balance of Loans Acquired (Details) - Investors Acquisition $ in Millions	Apr. 06, 2022 USD ($)
Business Acquisition [Line Items]
Unpaid Principal Balance	$ 20,560
Fair Value	20,139
Commercial
Business Acquisition [Line Items]
Unpaid Principal Balance	16,340
Fair Value	15,973
Commercial \| Commercial and industrial
Business Acquisition [Line Items]
Unpaid Principal Balance	3,021
Fair Value	2,899
Commercial \| Commercial real estate
Business Acquisition [Line Items]
Unpaid Principal Balance	13,310
Fair Value	13,065
Commercial \| Leases
Business Acquisition [Line Items]
Unpaid Principal Balance	9
Fair Value	9
Retail
Business Acquisition [Line Items]
Unpaid Principal Balance	4,220
Fair Value	4,166
Retail \| Residential mortgages
Business Acquisition [Line Items]
Unpaid Principal Balance	3,949
Fair Value	3,889
Retail \| Home equity
Business Acquisition [Line Items]
Unpaid Principal Balance	267
Fair Value	273
Retail \| Other retail
Business Acquisition [Line Items]
Unpaid Principal Balance	4
Fair Value	$ 4

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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- Definition

Fair value of acquired receivable from business combination, excluding certain loans and debt securities acquired in transfer.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)(1)
-URI https://asc.fasb.org/extlink&oid=128092470&loc=d3e4845-128472

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- Definition

For receivables acquired in a business combination, excluding certain loans and debt securities acquired in a transfer (as defined), this element represents the gross contractual amounts receivable, by major class of receivable, such as loans, direct finance leases (as defined), and any other class of receivables.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
-URI https://asc.fasb.org/extlink&oid=128092470&loc=d3e4845-128472

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