DEBT - Short-Term Borrowings (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Short-term Debt [Line Items]
Commercial paper	$ 18,173	$ 16,476
Other borrowings	36,778	28,573
Total short-term borrowings	54,951	45,049
Collateralized short-term advances from Federal Home Loan Bank	23,400	17,600
Bank
Short-term Debt [Line Items]
Commercial paper	12,157	10,155
Broker-dealer and other
Short-term Debt [Line Items]
Commercial paper	$ 6,016	$ 6,321

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 advances from Federal Home Loan Bank (FHLBank) maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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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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