DEBT - Short-Term Borrowings (Details) - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019
Short-term Debt [Line Items]
Commercial paper	$ 17,925	$ 16,476
Other borrowings	22,231	28,573
Total short-term borrowings	40,156	45,049
Collateralized short-term advances from Federal Home Loan Bank	12,000	17,600
Bank
Short-term Debt [Line Items]
Commercial paper	10,953	10,155
Broker-dealer and other
Short-term Debt [Line Items]
Commercial paper	$ 6,972	$ 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 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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