Net debt and net debt including leases - Disclosure of net debt including leases (Details) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018	Jun. 30, 2018
Subclassifications of assets, liabilities and equities [abstract]
Net debt	$ 46,501	$ 43,477	$ 38,658
Finance lease obligations at 31 December 2018	10,379	667	619
Net partner (receivable) payable for joint operation leases	(230)	0	0
Net debt including leases	$ 56,650	$ 44,144	$ 39,277

The amount of liabilities related to finance leases.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Note Expiry date 2019-01-01
-Name IAS
-Number 1
-IssueDate 2018-01-01
-Paragraph 55
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-02&anchor=para_55&doctype=Standard&book=b
-URIDate 2018-03-16

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Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant