LOANS - Corporate Loans Gross Credit Losses (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Financing Receivable, Credit Quality Indicator [Line Items]
Total	$ 2,690	$ 1,634
Corporate loans
Financing Receivable, Credit Quality Indicator [Line Items]
2024	1	1
2023	37	0
2022	9	0
2021	0	0
2020	0	0
Prior	33	0
Revolving line of credit arrangement	98	38
Total	178	39
Corporate loans \| Commercial and industrial
Financing Receivable, Credit Quality Indicator [Line Items]
2024	0	1
2023	0	0
2022	0	0
2021	0	0
2020	0	0
Prior	0	0
Revolving line of credit arrangement	76	35
Total	76	36
Corporate loans \| Financial institutions
Financing Receivable, Credit Quality Indicator [Line Items]
2024	0	0
2023	0	0
2022	0	0
2021	0	0
2020	0	0
Prior	1	0
Revolving line of credit arrangement	7	0
Total	8	0
Corporate loans \| Mortgage and real estate
Financing Receivable, Credit Quality Indicator [Line Items]
2024	1	0
2023	37	0
2022	9	0
2021	0	0
2020	0	0
Prior	17	0
Revolving line of credit arrangement	0	0
Total	64	0
Corporate loans \| Other
Financing Receivable, Credit Quality Indicator [Line Items]
2024	0	0
2023	0	0
2022	0	0
2021	0	0
2020	0	0
Prior	15	0
Revolving line of credit arrangement	15	3
Total	$ 30	$ 3

Amount, excluding accrued interest, of decrease in allowance for credit loss on financing receivable from writeoff. Excludes net investment in lease.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-6

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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-Name Accounting Standards Codification
-Section 50
-Paragraph 13
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-13

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-5

Reference 2: http://www.xbrl.org/2003/role/exampleRef
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