SECURITIES BORROWING AND LENDING - Narrative (Details) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Offsetting Assets [Line Items]
Security collateral received	$ 846.0	$ 509.0
Security collateral pledged	2,368.0	1,629.0
Amount re-pledged with clearing organizations to meet deposit requirements	430.7	231.2
Third Parties
Offsetting Assets [Line Items]
Security collateral received	1.0	18.4
Asset Pledged as Collateral
Offsetting Assets [Line Items]
Securities pledged	4,360.0	$ 4,360.0
Asset Pledged as Collateral \| Securities Sold under Agreements to Repurchase
Offsetting Assets [Line Items]
Securities pledged	6,340.0
Security collateral received	$ 845.0

Pledged Assets Separately Reported, Securities Pledged as Collateral with Clearing Organizations

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- Definition

The aggregate fair value as of the balance sheet date of financial instruments and other positions owned by the entity including: (1) mortgages, mortgage-backed and asset backed securities; (2) US government and agency obligations; (3) state and municipal government obligations; (4) other sovereign government debt; (5) corporate obligations; (6) corporate equities; (7) principal investments; (8) derivative contracts; and (9) physical commodities. Includes both pledged and unpledged holdings.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 940
-SubTopic 320
-Section 45
-Paragraph 2
-URI https://asc.fasb.org/extlink&oid=35711157&loc=d3e42546-110969

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- Definition

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.

+ References

No definition available.

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- Definition

Amount of obligation to return cash collateral under master netting arrangements that have not been offset against securities borrowed.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (d)(2)
-URI https://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 13
-URI https://asc.fasb.org/extlink&oid=99393222&loc=SL20226016-175313

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- Definition

Amount of right to receive cash collateral under master netting arrangements that have not been offset against securities loaned.

+ References

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