XML 355 R158.htm IDEA: XBRL DOCUMENT
v3.19.3.a.u2

Assets and liabilities held for sale - Additional information (Detail) - Assets and liabilities classified as held for sale [Member] $ in Millions | Dec. 31, 2018 USD ($)
--- | ---
Rossing Uranium Limited [Member] |
Disclosure Of Assets And Liabilities Held For Sale [Line Items] |
Ownership interest in subsidiary | $ 106
ISAL Smelter [Member] |
Disclosure Of Assets And Liabilities Held For Sale [Line Items] |
Ownership interest in subsidiary | $ 334

X
- Definition Disclosure Of Assets And Liabilities Held For Sale [Line Items] + References No definition available. + Details
Name: | rio_DisclosureOfAssetsAndLiabilitiesHeldForSaleLineItems
Namespace Prefix: | rio_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Net assets of assets held for sale. + References No definition available. + Details
Name: | rio_NetAssetsOfAssetsHeldForSale
Namespace Prefix: | rio_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Details
Name: | ifrs-full_AssetsAndLiabilitiesClassifiedAsHeldForSaleAxis=ifrs-full_AssetsAndLiabilitiesClassifiedAsHeldForSaleMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

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