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.

No definition available.

+ Details

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- Definition

The proportion of ownership interest in a joint venture attributable to the entity. [Refer: Joint ventures [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 27
-IssueDate 2019-01-01
-Paragraph 17
-Subparagraph b
-Clause iii
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=27&code=ifrs-tx-2019-en-r&anchor=para_17_b_iii&doctype=Standard
-URIDate 2019-03-27

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 27
-IssueDate 2019-01-01
-Paragraph 16
-Subparagraph b
-Clause iii
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=27&code=ifrs-tx-2019-en-r&anchor=para_16_b_iii&doctype=Standard
-URIDate 2019-03-27

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 12
-IssueDate 2019-01-01
-Paragraph 21
-Subparagraph a
-Clause iv
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=12&code=ifrs-tx-2019-en-r&anchor=para_21_a_iv&doctype=Standard
-URIDate 2019-03-27

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- Definition

The proportion of the voting rights in a joint venture held by the entity. [Refer: Joint ventures [member]]

+ References

+ Details

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- Definition

The number of shares in the entity held by the entity or by its subsidiaries or associates. [Refer: Associates [member]; Subsidiaries [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2019-01-01
-Paragraph 79
-Subparagraph a
-Clause vi
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2019-en-r&anchor=para_79_a_vi&doctype=Standard
-URIDate 2019-03-27

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- Details

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- Details

Name:	ifrs-full_JointVenturesAxis=rio_SoharAluminiumCoLlcMember
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Principal joint ventures - Summary of joint ventures (Detail) - shares	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure of joint ventures [line items]
Number of shares held	0	0	0
Minera Escondida Limitada [Member]
Disclosure of joint ventures [line items]
Group interest (%)	30.00%
Sohar Aluminium Co. L.L.C.
Disclosure of joint ventures [line items]
Group interest (%)	20.00%
Sohar Aluminium Co. L.L.C. \| Ordinary [Member]
Disclosure of joint ventures [line items]
Number of shares held	37,500
Proportion of class held (%)	20.00%
Group interest (%)	20.00%