XML 329 R126.htm IDEA: XBRL DOCUMENT v3.10.0.1

Taxation - Summary of prima facie tax reconciliation (Parenthetical) (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Reconciliation Of Accounting Profit Multiplied By Applicable Tax Rates [Abstract]
UK tax payable (receivable) rate	19.00%	19.00%	20.00%
Groups share of profit of equity accounted units net of tax	$ 273	$ 191	$ 156

X

- Definition

The applicable income tax rate.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 12
-IssueDate 2017-01-01
-Paragraph 81
-Subparagraph c
-Clause ii
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=12&date=2017-03-01&anchor=para_81_c_ii&doctype=Standard
-URIDate 2017-03-09

+ Details

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Balance Type:	na
Period Type:	duration

X

- References

No definition available.

+ Details

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X

- Definition

Income tax on share of profit of equity accounted units.

+ References

No definition available.

+ Details

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Namespace Prefix:	rio_
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Balance Type:	debit
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