XML 427 R224.htm IDEA: XBRL DOCUMENT
v3.10.0.1

Principal joint ventures - Summary of joint ventures (Parenthetical) (Detail) | 12 Months Ended
--- | ---
Dec. 31, 2018 | Dec. 31, 2017
Minera Escondida Limitada [member] |  |
Disclosure Of Joint Ventures [Line Items] |  |
Group interest (%), Joint Venture | 30.00% | 30.00%
Minera Escondida Limitada [member] | BHP Billiton Member |  |
Disclosure Of Joint Ventures [Line Items] |  |
Ownership interest in joint venture held by joint partner | 57.50% |
Sohar Aluminium Co. L.L.C. [member] |  |
Disclosure Of Joint Ventures [Line Items] |  |
Group interest (%), Joint Venture | 20.00% | 20.00%

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_DisclosureOfJointVenturesLineItems
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- 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 2017-01-01 -Paragraph 17 -Subparagraph b -Clause iii -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=27&date=2017-03-01&anchor=para_17_b_iii&doctype=Standard -URIDate 2017-03-09 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 27 -IssueDate 2017-01-01 -Paragraph 16 -Subparagraph b -Clause iii -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=27&date=2017-03-01&anchor=para_16_b_iii&doctype=Standard -URIDate 2017-03-09 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 12 -IssueDate 2017-01-01 -Paragraph 21 -Subparagraph a -Clause iv -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=12&date=2017-03-01&anchor=para_21_a_iv&doctype=Standard -URIDate 2017-03-09 + Details
Name: | ifrs-full_ProportionOfOwnershipInterestInJointVenture
Namespace Prefix: | ifrs-full_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Proportion of ownership interest in joint venture held by joint partner. + References No definition available. + Details
Name: | rio_ProportionOfOwnershipInterestInJointVentureHeldByJointPartner
Namespace Prefix: | rio_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | ifrs-full_JointVenturesAxis=rio_MineraEscondidaLimitadaMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_CategoriesOfRelatedPartiesAxis=rio_BhpBillitonMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_JointVenturesAxis=rio_SoharAluminiumCoLlcMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |