ACQUISITION OF BUSINESSES - Schedule of Prior Year Acquisitions (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Disclosure of detailed information about business combination [line items]
Goodwill	$ 1,554	$ 1,152
Business services
Disclosure of detailed information about business combination [line items]
Goodwill	579	238
Various acquisitions \| Business services
Disclosure of detailed information about business combination [line items]
Total Consideration	211	19
Net working capital		1
Intangible assets	403	36
Goodwill	325	39
Net assets acquired before non-controlling interest	1,053	76
Non-controlling interest	(842)	(57)
Net Assets Acquired	$ 211	$ 19

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Net Working Capital Recognised As Of Acquisition Date

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The fair value, at acquisition date, of the consideration transferred in a business combination. [Refer: Business combinations [member]]

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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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The amount of assets representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognised. [Refer: Business combinations [member]]

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The amount recognised as of the acquisition date for net identifiable assets acquired or liabilities assumed in a business combination. [Refer: Business combinations [member]]

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The amount recognised as of the acquisition date for identifiable intangible assets acquired in a business combination. [Refer: Intangible assets other than goodwill; Business combinations [member]]

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The amount of non-controlling interest in the acquiree recognised at the acquisition date for business combinations in which the acquirer holds less than 100 per cent of the equity interests in the acquiree at the acquisition date. [Refer: Business combinations [member]]

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