SECURITIES BORROWED, LOANED AND SUBJECT TO REPURCHASE AGREEMENTS - Securities (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Federal Funds Purchased and Securities Sold under Agreements to Repurchase [Abstract]
Securities purchased under agreements to resell	$ 178,930	$ 169,874
Deposits paid for securities borrowed	83,606	81,448
Total	262,536	251,322
Securities sold under agreements to repurchase	213,525	155,164
Deposits received for securities loaned	8,799	11,175
Total	222,324	166,339
Securities-for-securities lending transactions	$ 9,200	$ 6,300

Carrying value of federal funds purchased and securities sold under repurchase agreements and deposits received for securities loaned.

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Carrying value of federal funds sold, securities purchased under agreements to resell, and deposits paid for securities borrowed.

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This is the amount of cash advanced as security in return for borrowing securities from another party.

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The amount of cash received as security in return for loaning securities to another party.

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Amount, after the effects of master netting arrangements, of funds outstanding loaned in the form of a security resale agreement between the entity and another party for the purchase and resale of identical or substantially the same securities at a date certain for a specified price. Includes purchases of participations in pools of securities that are subject to a resale agreement, assets not subject to a master netting arrangement and not elected to be offset.

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The carrying value as of the balance sheet date of the assets received as collateral against securities loaned to other broker-dealers. Borrowers of securities generally are required to provide collateral to the lenders of securities, commonly cash but sometimes other securities or standby letters of credit, with a value slightly higher than that of the securities borrowed. In instances where the entity is permitted to sell or re-pledge these securities, the entity reports the fair value of the collateral received and the related obligation to return the collateral as a liability.

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Amount, after the effects of master netting arrangements, of funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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