CONTRACTS IN PROGRESS (Details) - USD ($) $ in Millions	Jun. 30, 2018	Dec. 31, 2017
Construction Contracts [Abstract]
Contract costs incurred to date	$ 12,949	$ 12,129
Profit recognized to date (less recognized losses)	241	558
Contract costs incurred and profit recognized (less recognized losses)	13,190	12,687
Less: progress billings	(13,786)	(12,919)
Contract work in progress (liability)	(596)	(232)
Comprising:
Amounts due from customers — work in progress (current)	118	195
Amounts due to customers — creditors (current / non-current)	(714)	(427)
Contract work in progress (liability)	$ (596)	$ (232)

Construction Contracts [Abstract]

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Construction In Progress [Abstract]

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Construction In Progress, Excluding Progress Billings

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Recognized Profits Less Recognized Losses For Contracts In Progress

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The amount of expenditure capitalised during the construction of non-current assets that are not yet available for use. [Refer: Non-current assets]

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The aggregate amount of costs incurred and recognised profits, less recognised losses, to date on construction contracts in progress.

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The amount recognised as an asset as the net of: (a) costs incurred plus recognised profits; less (b) the sum of recognised losses and progress billings for all contracts in progress for which costs incurred plus recognised profits (less recognised losses) exceeds progress billings.

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The amount recognised as a liability as the net of: (a) costs incurred plus recognised profits; less (b) the sum of recognised losses and progress billings for all contracts in progress for which progress billings exceed costs incurred plus recognised profits (less recognised losses).

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The amounts billed for work performed on a construction contract whether or not they have been paid by the customer.

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