DEBT - Short-Term Borrowings (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Short-term Debt [Line Items]
Commercial paper	$ 17,012	$ 18,010
Other borrowings	12,671	11,504
Total short-term borrowings	29,683	29,514
Collateralized short-term advances from Federal Home Loan Bank	1	4,000
Bank
Short-term Debt [Line Items]
Commercial paper	10,017	10,022
Broker-dealer and other
Short-term Debt [Line Items]
Commercial paper	$ 6,995	$ 7,988

Carrying value as of the balance sheet date of short-term borrowings using unsecured obligations issued by banks, corporations and other borrowers to investors. The maturities of these money market securities generally do not exceed 270 days.

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Amount of advance from Federal Home Loan Bank (FHLBank) maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of borrowings classified as other, maturing within one year or the normal operating cycle, if longer.

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