XML 256 R249.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Share-based payments -Summary of performance share plans (Detail) | 12 Months Ended
--- | ---
Dec. 31, 2017 GBP (£) shares AUD ($) | Dec. 31, 2017 AUD ($) shares | Dec. 31, 2016 GBP (£) shares | Dec. 31, 2016 AUD ($) shares
Rio Tinto Limited [member] |  |  |  |
Disclosure Of Terms And Conditions Of Sharebased Payment Arrangement [Line Items] |  |  |  |
Number of transfers from equity to cash settled | (276,722) | (276,722) |  |
Performance share plans [member] | Rio Tinto plc [member] |  |  |  |
Disclosure Of Terms And Conditions Of Sharebased Payment Arrangement [Line Items] |  |  |  |
Weighted average fair value at grant date, non-vested shares at beginning balance | £ | £ 18.27 |  | £ 21.29 |
Weighted average fair value at grant date, non-vested shares, awarded | £ | 24.64 |  | 12.81 |
Weighted average fair value at grant date, non-vested shares, forfeited | £ | 16.28 |  | 17.22 |
Weighted average fair value at grant date, non-vested shares, failed performance conditions | £ | 16.25 |  | 24.61 |
Weighted average fair value at grant date, non-vested shares, vested | £ | 21.51 |  | 24.61 |
Weighted average fair value at grant date, non-vested shares at ending balance | £ | £ 20.47 |  | £ 18.27 |
Number of non-vested shares at beginning balance | £ | 2,883,053 |  | 2,988,454 |
Number of non-vested shares, awarded | £ | 1,198,677 |  | 1,085,974 |
Number of non-vested shares, forfeited | £ | (199,435) |  | (603,871) |
Number of non-vested shares, failed performance conditions | £ | (161,966) |  | (203,491) |
Number of non-vested shares, vested | £ | (165,055) |  | (384,013) |
Number of non-vested shares at ending balance | £ | 3,555,274 |  | 2,883,053 |
Weighted average share price, Vested awards settled in shares during the year (including dividend shares applied on vesting) | £ | £ 31.04 |  | £ 19.08 |
Weighted average share price, Vested awards settled in cash during the year (including dividend shares applied on vesting) | £ |  |  | £ 19.00 |
Number of vested awards settled in shares during the year (including dividend shares applied on vesting) | shares | 188,383 | 188,383 | 368,623 | 368,623
Number of vested awards settled in cash during the year (including dividend shares applied on vesting) | shares |  |  | 486 | 486
Performance share plans [member] | Rio Tinto Limited [member] |  |  |  |
Disclosure Of Terms And Conditions Of Sharebased Payment Arrangement [Line Items] |  |  |  |
Weighted average fair value at grant date, non-vested shares at beginning balance |  | $ 37.52 |  | $ 41.13
Weighted average fair value at grant date, non-vested shares, awarded |  | 45.84 |  | 28.66
Weighted average fair value at grant date, non-vested shares, forfeited |  | 36.59 |  | 36.18
Weighted average fair value at grant date, non-vested shares, failed performance conditions |  | 30.89 |  | 44.71
Weighted average fair value at grant date, non-vested shares, vested |  | 40.79 |  | 44.71
Weighted average fair value transfers from equity to cash settled |  | 40.11 |  |
Weighted average fair value at grant date, non-vested shares at ending balance |  | $ 40.13 |  | $ 37.52
Number of non-vested shares at beginning balance |  | 1,590,957 |  | 2,048,823
Number of non-vested shares, awarded |  | 529,776 |  | 535,418
Number of non-vested shares, forfeited |  | (36,716) |  | (526,212)
Number of non-vested shares, failed performance conditions |  | (113,857) |  | (161,937)
Number of non-vested shares, vested |  | (84,284) |  | (305,135)
Number of non-vested shares at ending balance |  | 1,609,154 |  | 1,590,957
Weighted average share price, Vested awards settled in shares during the year (including dividend shares applied on vesting) |  | $ 63.09 |  | $ 42.99
Weighted average share price, Vested awards settled in cash during the year (including dividend shares applied on vesting) |  | $ 62.81 |  | $ 43.47
Number of vested awards settled in shares during the year (including dividend shares applied on vesting) | shares | 73,311 | 73,311 | 284,507 | 284,507
Number of vested awards settled in cash during the year (including dividend shares applied on vesting) | shares | 5,010 | 5,010 | 847 | 847

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

X
- Definition The number of other equity instruments (ie other than share options) granted in a share-based payment arrangement. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 2 -IssueDate 2016-01-13 -Paragraph 47 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=2&date=2016-03-30&anchor=para_47_b&doctype=Standard -URIDate 2016-03-31 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Name IFRS -Number 2 -IssueDate 2016-01-13 -Paragraph 45 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=2&date=2016-03-30&anchor=para_45&doctype=Standard -URIDate 2016-03-31 + Details
Name: | ifrs-full_NumberOfInstrumentsOtherEquityInstrumentsGranted
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | duration

X
- Definition The number of other equity instruments (ie other than share options) exercised or vested in a share-based payment arrangement. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IFRS -Number 2 -IssueDate 2016-01-13 -Paragraph 45 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=2&date=2016-03-30&anchor=para_45&doctype=Standard -URIDate 2016-03-31 + Details
Name: | ifrs-full_NumberOfOtherEquityInstrumentsExercisedOrVestedInSharebasedPaymentArrangement
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | duration

X
- Definition The number of other equity instruments (ie other than share options) forfeited in a share-based payment arrangement. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IFRS -Number 2 -IssueDate 2016-01-13 -Paragraph 45 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=2&date=2016-03-30&anchor=para_45&doctype=Standard -URIDate 2016-03-31 + Details
Name: | ifrs-full_NumberOfOtherEquityInstrumentsForfeitedInSharebasedPaymentArrangement
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | duration

X
- Definition The number of other equity instruments (ie other than share options) outstanding in a share-based payment arrangement. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IFRS -Number 2 -IssueDate 2016-01-13 -Paragraph 45 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=2&date=2016-03-30&anchor=para_45&doctype=Standard -URIDate 2016-03-31 + Details
Name: | ifrs-full_NumberOfOtherEquityInstrumentsOutstandingInSharebasedPaymentArrangement
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | instant

X
- Definition The weighted average exercise price of other equity instruments (ie other than share options) exercised or vested in a share-based payment arrangement. [Refer: Weighted average [member]] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IFRS -Number 2 -IssueDate 2016-01-13 -Paragraph 45 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=2&date=2016-03-30&anchor=para_45&doctype=Standard -URIDate 2016-03-31 + Details
Name: | ifrs-full_WeightedAverageExercisePriceOfOtherEquityInstrumentsExercisedOrVestedInSharebasedPaymentArrangement
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | duration

X
- Definition The weighted average exercise price of other equity instruments (ie other than share options) forfeited in a share-based payment arrangement. [Refer: Weighted average [member]] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IFRS -Number 2 -IssueDate 2016-01-13 -Paragraph 45 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=2&date=2016-03-30&anchor=para_45&doctype=Standard -URIDate 2016-03-31 + Details
Name: | ifrs-full_WeightedAverageExercisePriceOfOtherEquityInstrumentsForfeitedInSharebasedPaymentArrangement
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | duration

X
- Definition The weighted average exercise price of other equity instruments (ie other than share options) granted in a share-based payment arrangement. [Refer: Weighted average [member]] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IFRS -Number 2 -IssueDate 2016-01-13 -Paragraph 45 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=2&date=2016-03-30&anchor=para_45&doctype=Standard -URIDate 2016-03-31 + Details
Name: | ifrs-full_WeightedAverageExercisePriceOfOtherEquityInstrumentsGrantedInSharebasedPaymentArrangement
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | duration

X
- Definition The weighted average exercise price of other equity instruments (ie other than share options) outstanding in a share-based payment arrangement. [Refer: Weighted average [member]] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IFRS -Number 2 -IssueDate 2016-01-13 -Paragraph 45 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=2&date=2016-03-30&anchor=para_45&doctype=Standard -URIDate 2016-03-31 + Details
Name: | ifrs-full_WeightedAverageExercisePriceOfOtherEquityInstrumentsOutstandingInSharebasedPaymentArrangement
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | instant

X
- Definition Number of cash-settled awards vested in share-based payment arrangement. + References No definition available. + Details
Name: | rio_NumberOfCashsettledAwardsVestedInSharebasedPaymentArrangement
Namespace Prefix: | rio_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of equity-settled awards vested in share-based payment arrangement. + References No definition available. + Details
Name: | rio_NumberOfEquitysettledAwardsVestedInSharebasedPaymentArrangement
Namespace Prefix: | rio_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of no-vested shares failed performance conditions in share-based payment arrangement. + References No definition available. + Details
Name: | rio_NumberOfNovestedSharesFailedPerformanceConditionsInSharebasedPaymentArrangement
Namespace Prefix: | rio_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of transfers from equity to cash settled. + References No definition available. + Details
Name: | rio_NumberOfTransfersFromEquityToCashSettled
Namespace Prefix: | rio_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | instant

X
- Definition Weighted average fair value at grant date of non-vested shares failed performance conditions in share-based payment arrangement. + References No definition available. + Details
Name: | rio_WeightedAverageFairValueAtGrantDateOfNonvestedSharesFailedPerformanceConditionsInSharebasedPaymentArrangement
Namespace Prefix: | rio_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | duration

X
- Definition Weighted average fair value transfers from equity to cash settled. + References No definition available. + Details
Name: | rio_WeightedAverageFairValueTransfersFromEquityToCashSettled
Namespace Prefix: | rio_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | duration

X
- Definition Weighted average share price of cash-settled awards vested in share-based payment arrangement. + References No definition available. + Details
Name: | rio_WeightedAverageSharePriceOfCashsettledAwardsVestedInSharebasedPaymentArrangement
Namespace Prefix: | rio_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | duration

X
- Definition Weighted average share price of equity-settled awards vested in share-based payment arrangement. + References No definition available. + Details
Name: | rio_WeightedAverageSharePriceOfEquitysettledAwardsVestedInSharebasedPaymentArrangement
Namespace Prefix: | rio_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | dei_LegalEntityAxis=rio_RioTintoLimitedMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_TypesOfSharebasedPaymentArrangementsAxis=rio_PerformanceSharePlansMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_LegalEntityAxis=rio_RioTintoPlcMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |