The amount of expense relating to restructuring. Restructuring is a programme that is planned and controlled by management and materially changes either the scope of a business undertaken by an entity or the manner in which that business is conducted. Such programmes include: (a) the sale or termination of a line of business; (b) closure of business locations in a country or region or the relocation of activities from one country or region to another; (c) changes in management structure; and (d) fundamental reorganisations that have a material effect on the nature and focus of the entity's operations.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2017-01-01
-Paragraph 98
-Subparagraph b
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_98_b&doctype=Standard
-URIDate 2017-03-09

Name:	ifrs-full_ExpenseOfRestructuringActivities
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

POST BALANCE SHEET EVENTS (Details) - USD ($) $ in Millions	12 Months Ended
POST BALANCE SHEET EVENTS (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Disclosure of non-adjusting events after reporting period
Charge for programme			$ 62	$ 65
Accelerating Performance and Execution programme
Disclosure of non-adjusting events after reporting period
Time period for enhancement programme		5 years
Expected one-off cash cost for programme		$ 240
Provision for programme		$ 0
Accelerating Performance and Execution programme \| Forecast
Disclosure of non-adjusting events after reporting period
Charge for programme	$ 100