XML 271 R68.htm IDEA: XBRL DOCUMENT
v3.10.0.1

Goodwill (Tables) | 12 Months Ended
--- | ---
Dec. 31, 2018
Goodwill [Abstract] |
Summary of goodwill |
|  | 2018 |  |  | 2017 |
| US$m |  | US$m |
Net book value |  |  |  |  |  |
At 1 January |  | 1,037 |  |  | 951 |
Adjustment on currency translation |  | (125 | ) |  | 86 |
At 31 December |  | 912 |  |  | 1,037 |
– cost |  | 15,861 |  |  | 17,942 |
– accumulated impairment |  | (14,949 | ) |  | (16,905 | )
At 1 January |  |  |  |  |  |
– cost |  | 17,942 |  |  | 17,144 |
– accumulated impairment |  | (16,905 | ) |  | (16,193 | )
At 31 December, goodwill has been allocated as follows: |  |  |  |  |  |
|  | 2018 |  |  | 2017 |
| US$m |  | US$m |
Net book value |  |  |  |  |  |
Richards Bay Minerals |  | 474 |  |  | 552 |
Pilbara |  | 351 |  |  | 389 |
Dampier Salt |  | 87 |  |  | 96 |
|  | 912 |  |  | 1,037 |
Key assumptions calculation of fair value less costs of disposal | The key assumptions to which the calculation of FVLCD for Richards Bay Minerals is most sensitive and the corresponding decrease in FVLCD are set out below:
| US$m
5% decrease in the titanium slag price | 174
1% increase in the discount rate applied to post-tax cash flows | 195
10% strengthening of the South African rand | 328

X
- Definition The disclosure of the reconciliation of changes in goodwill. [Refer: Goodwill] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 3 -IssueDate 2017-01-01 -Paragraph B67 -Subparagraph d -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=3&date=2017-03-01&anchor=para_B67_d&doctype=Appendix&seq=2 -URIDate 2017-03-09 + Details
Name: | ifrs-full_DisclosureOfReconciliationOfChangesInGoodwillExplanatory
Namespace Prefix: | ifrs-full_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition The disclosure of key assumptions calculation of fair value less costs of disposal. + References No definition available. + Details
Name: | rio_DisclosureOfKeyAssumptionsCalculationOfFairValueLessCostsOfDisposalExplanatory
Namespace Prefix: | rio_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Goodwill. + References No definition available. + Details
Name: | rio_GoodwillAbstract
Namespace Prefix: | rio_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration