Restructuring costs (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Restructuring programmes
Total charge	$ 92	$ 184	$ 187	$ 496
Cost of sales
Restructuring programmes
Total charge	23	43	55	81
Research and development expense
Restructuring programmes
Total charge	31	38	58	142
Selling, general and administrative costs
Restructuring programmes
Total charge	48	$ 103	84	197
Other operating income and expense
Restructuring programmes
Total charge	$ (10)		$ (10)	$ 76

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

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