SECURITIZATIONS AND VARIABLE INTEREST ENTITIES - Loan Delinquencies and Liquidation Losses (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Mortgage securitizations - Non-agency-sponsored
Variable Interest Entity
Securitized assets past due	$ 55,400.0	$ 40,800.0
Securitized assets liquidation losses	10.6	26.2
Mortgage securitizations - Non-agency-sponsored \| 90 days past due
Variable Interest Entity
Securitized assets past due	400.0	500.0
Residential mortgages
Variable Interest Entity
Securitized assets past due	29,200.0	16,900.0
Securitized assets liquidation losses	10.6	26.2
Residential mortgages \| 90 days past due
Variable Interest Entity
Securitized assets past due	400.0	500.0
Commercial and other
Variable Interest Entity
Securitized assets past due	26,200.0	23,900.0
Securitized assets liquidation losses	0.0	0.0
Commercial and other \| 90 days past due
Variable Interest Entity
Securitized assets past due	0.0	$ 0.0
Personal loan
Variable Interest Entity
Securitized assets past due	$ 200.0

This is the principal amount of loans (across all types of loans) that are overdue in payment by a set number of days.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (e)(4)
-URI http://asc.fasb.org/extlink&oid=121570589&loc=d3e107314-111719

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Amount of credit loss after recoveries for transferred financial assets that continue to be recognized in the statement of financial position.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (e)(5)
-URI http://asc.fasb.org/extlink&oid=121570589&loc=d3e107314-111719

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- Definition

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+ References

No definition available.

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