DERIVATIVES - Net Investment Hedges (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Net Investment Hedging \| Foreign currency translation adjustment (CTA), net of hedges
Derivative gain (losses)
Gain (loss) recognized in OCI, effective portion, net	$ (741)	$ (134)	$ 1,419	$ (298)

Amount before tax and reclassification adjustments of other comprehensive income (loss).

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-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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