OFFSETTING ASSETS AND LIABILITIES - NARRATIVE (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2022	Dec. 31, 2021
Offsetting Assets [Line Items]
Fair value of securities re-pledged	$ 7,230.0	$ 9,210.0
Security collateral received	0.6	$ 0.3
Amount re-pledged with clearing organizations to meet deposit requirements	$ 234.0
Agreement One
Offsetting Assets [Line Items]
Contractual term	30 days
Contractual obligation	$ 25.0
Agreement Two
Offsetting Assets [Line Items]
Contractual term	21 days
Contractual obligation	$ 35.0

Contractual Obligation, Contractual Term

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- Definition

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

+ References

No definition available.

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- Definition

Amount of contractual obligation, including but not limited to, long-term debt, capital lease obligations, operating lease obligations, purchase obligations, and other commitments.

+ References

No definition available.

+ Details

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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

The sum of the fair values, as of the date of each statement of financial position presented, of securities that are restricted as collateral for the payment of related debt obligations, primarily secured borrowings and repurchase agreements, and that are reclassified and separately reported in the statement of financial position because the transferee has the right by contract or custom to sell or re-pledge them.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=66007379&loc=d3e113888-111728

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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 http://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 http://asc.fasb.org/extlink&oid=99393222&loc=SL20226016-175313

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