XML 207 R200.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Financial instruments and risk management - Summary by currency, Group's net debt, after taking into account relevant cross currency interest rate swaps and foreign exchange contracts (Detail) - USD ($) $ in Millions | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
--- | --- | --- | ---
Disclosure Of Financial Instruments [Line Items] |  |  |
Cash and cash equivalents | $ 10,550 | $ 8,201 |
Total borrowings in note 22 | (15,176) | (17,630) |
Derivatives related to net debt | (276) | (516) |
Net funds/(debt) | (3,845) | (9,587) | $ (13,783)
Foreign exchange risk [member] |  |  |
Disclosure Of Financial Instruments [Line Items] |  |  |
Cash and cash equivalents | 10,550 |  |
Other investments | 958 |  |
Total borrowings in note 22 | (15,176) |  |
Derivatives related to net debt | (177) |  |
Net funds/(debt) | (3,845) | (9,587) |
Foreign exchange risk [member] | US Dollars [Member] |  |  |
Disclosure Of Financial Instruments [Line Items] |  |  |
Cash and cash equivalents | 9,950 |  |
Other investments | 958 |  |
Total borrowings in note 22 | (14,359) |  |
Derivatives related to net debt | (177) |  |
Net funds/(debt) | (3,628) | (9,294) |
Foreign exchange risk [member] | Australian Dollars [Member] |  |  |
Disclosure Of Financial Instruments [Line Items] |  |  |
Cash and cash equivalents | 332 |  |
Total borrowings in note 22 | (540) |  |
Net funds/(debt) | (208) | (313) |
Foreign exchange risk [member] | Euro Member Countries, Euro |  |  |
Disclosure Of Financial Instruments [Line Items] |  |  |
Cash and cash equivalents | 49 |  |
Total borrowings in note 22 | (107) |  |
Net funds/(debt) | (58) | (62) |
Foreign exchange risk [member] | South Africa, Rand |  |  |
Disclosure Of Financial Instruments [Line Items] |  |  |
Cash and cash equivalents | 59 |  |
Net funds/(debt) | 59 | 103 |
Foreign exchange risk [member] | Canada, Dollars [Member] |  |  |
Disclosure Of Financial Instruments [Line Items] |  |  |
Cash and cash equivalents | 18 |  |
Total borrowings in note 22 | (166) |  |
Net funds/(debt) | (148) | (155) |
Foreign exchange risk [member] | Other Currencies [member] |  |  |
Disclosure Of Financial Instruments [Line Items] |  |  |
Cash and cash equivalents | 142 |  |
Total borrowings in note 22 | (4) |  |
Net funds/(debt) | $ 138 | $ 134 |

X
- Definition The amount of outstanding funds that the entity is obligated to repay. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2016-01-13 -Paragraph 55 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2016-03-30&anchor=para_55&doctype=Standard -URIDate 2016-03-31 + Details
Name: | ifrs-full_Borrowings
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The amount of cash on hand and demand deposits, along with short-term, highly liquid investments that are readily convertible to known amounts of cash and that are subject to an insignificant risk of changes in value. [Refer: Cash; Cash equivalents] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 7 -IssueDate 2016-01-13 -Paragraph 45 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=7&date=2016-03-30&anchor=para_45&doctype=Standard -URIDate 2016-03-31 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 12 -IssueDate 2016-01-13 -Paragraph B13 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=12&date=2016-03-30&anchor=para_B13_a&doctype=Appendix&seq=2 -URIDate 2016-03-31 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2016-01-13 -Paragraph 54 -Subparagraph i -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2016-03-30&anchor=para_54_i&doctype=Standard -URIDate 2016-03-31 + Details
Name: | ifrs-full_CashAndCashEquivalents
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

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

X
- Definition Derivative financial liabilities related to net debt. + References No definition available. + Details
Name: | rio_DerivativeFinancialLiabilitiesRelatedToNetDebt
Namespace Prefix: | rio_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The amount of net debt of the entity. + References No definition available. + Details
Name: | rio_NetDebt
Namespace Prefix: | rio_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Other investment. + References No definition available. + Details
Name: | rio_OtherInvestment
Namespace Prefix: | rio_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | ifrs-full_TypesOfRisksAxis=ifrs-full_CurrencyRiskMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | rio_CurrenciesAxis=currency_USD
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | rio_CurrenciesAxis=currency_AUD
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | rio_CurrenciesAxis=currency_EUR
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | rio_CurrenciesAxis=currency_ZAR
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | rio_CurrenciesAxis=currency_CAD
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | rio_CurrenciesAxis=rio_OtherCurrencyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |