XML 209 R127.htm IDEA: XBRL DOCUMENT v3.19.3.a.u2

Earnings per ordinary share - Summary of earnings (loss) per ordinary shares (Footnotes) (Detail) - shares shares in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Earnings per share [line items]
Weighted average number of shares outstanding	1,630.1	1,719.3	1,786.7
Effect of dilutive securities shares	12.0	12.4	12.8
Rio Tinto plc [Member]
Earnings per share [line items]
Weighted average number of shares outstanding	1,259.4	1,312.7	1,364.5
Rio Tinto Limited [Member]
Earnings per share [line items]
Weighted average number of shares outstanding	370.7	406.6	422.3

X

- Definition

The number of dilutive potential ordinary shares that relate to the assumed exercise of the entity's share options.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 33
-IssueDate 2019-01-01
-Paragraph 70
-Subparagraph b
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=33&code=ifrs-tx-2019-en-r&anchor=para_70_b&doctype=Standard
-URIDate 2019-03-27

+ Details

Name:	ifrs-full_DilutiveEffectOfShareOptionsOnNumberOfOrdinaryShares
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table.

+ References

No definition available.

+ Details

Name:	ifrs-full_EarningsPerShareLineItems
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

The number of ordinary shares outstanding at the beginning of the period, adjusted by the number of ordinary shares bought back or issued during the period multiplied by a time-weighting factor.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 33
-IssueDate 2019-01-01
-Paragraph 70
-Subparagraph b
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=33&code=ifrs-tx-2019-en-r&anchor=para_70_b&doctype=Standard
-URIDate 2019-03-27

+ Details

Name:	ifrs-full_WeightedAverageShares
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

X

- Details

Name:	dei_LegalEntityAxis=rio_RioTintoPlcMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	dei_LegalEntityAxis=rio_RioTintoLimitedMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: