DEBT - Short-Term Borrowings (Details) - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
Debt Disclosure [Abstract]
Commercial paper	$ 12,051	$ 9,940
Other borrowings	21,719	34,512
Total short-term borrowings	33,770	44,452
Collateralized short-term advances from Federal Home Loan Bank	$ 10,500	$ 23,800

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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-SubTopic 210
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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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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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