DERIVATIVE FINANCIAL INSTRUMENTS - Notional Amount of Derivative Positions (Details) - USD ($) $ in Millions	Jun. 30, 2018	Dec. 31, 2017
Foreign exchange contracts
Disclosure of detailed information about hedging instruments [line items]
Notional amount of derivative positions	$ 1,597	$ 1,243

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table.

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