FINANCIAL INSTRUMENTS - Assets and Liabilities Not Carried at Fair Value (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Financial assets
Credit card and loan receivables, net	$ 16,432.6	$ 19,126.0
Credit card and loan receivables held for sale	91.5	436.2
Total assets measured at fair value	16,524.1	19,562.2
Financial liabilities
Deposits	11,575.1	12,303.6
Non-recourse borrowings of consolidated securitization entities	6,365.0	7,333.6
Long-term and other debt	2,903.3	2,878.8
Total liabilities measured at fair value	20,843.4	22,516.0
Level 2
Financial liabilities
Deposits	11,575.1	12,303.6
Non-recourse borrowings of consolidated securitization entities	6,365.0	7,333.6
Long-term and other debt	2,903.3	2,878.8
Total liabilities measured at fair value	20,843.4	22,516.0
Level 3
Financial assets
Credit card and loan receivables, net	16,432.6	19,126.0
Credit card and loan receivables held for sale	91.5	436.2
Total assets measured at fair value	$ 16,524.1	$ 19,562.2

Fair value amount of loans and leases held for sale in portfolio.

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Fair value amount of loans and leases held in portfolio.

+ References

No definition available.

+ Details

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- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents non-recourse borrowings of consolidated securitization entities.

+ References

No definition available.

+ Details

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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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- References

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- Definition

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=118260190&loc=d3e13433-108611

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- Definition

Fair value portion of deposit liabilities held by the entity, including, but not limited to, foreign and domestic, interest and noninterest bearing, demand deposits, saving deposits, negotiable orders of withdrawal (NOW) and time deposits.

+ References

No definition available.

+ Details

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- Definition

Fair value of financial and nonfinancial obligations.

+ References

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- References

No definition available.

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