XML 79 R72.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Intangible assets (Tables) | 12 Months Ended
--- | ---
Dec. 31, 2017
Intangible Assets [Abstract] |
Summary of intangible assets |
|  |  |  | Trademarks, |  | Contract |  |  |  |  |  |  |
| Exploration |  | patented and |  | based |  | Other |  |  |  |
| and |  | non-patented |  | intangible |  | intangible |  |  |  |
| evaluation (a) |  | technology |  | assets (b) |  | assets |  | Total |
Year ended 31 December 2017 | US$m |  | US$m |  | US$m |  | US$m |  | US$m |
Net book value |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
At 1 January 2017 |  | 711 |  |  | 78 |  |  | 2,103 |  |  | 387 |  |  | 3,279 |
Adjustment on currency translation |  | 27 |  |  | 10 |  |  | 150 |  |  | 29 |  |  | 216 |
Expenditure during the year |  | 57 |  |  | - |  |  | - |  |  | 65 |  |  | 122 |
Amortisation for the year (c) |  | - |  |  | (13 | ) |  | (67 | ) |  | (97 | ) |  | (177 | )
Impairment charges (d) |  | (357 | ) |  | - |  |  | - |  |  | - |  |  | (357 | )
Disposals, transfers and other movements (e) |  | (45 | ) |  | - |  |  | 2 |  |  | 79 |  |  | 36 |
At 31 December 2017 |  | 393 |  |  | 75 |  |  | 2,188 |  |  | 463 |  |  | 3,119 |
– cost |  | 2,658 |  |  | 224 |  |  | 3,438 |  |  | 1,537 |  |  | 7,857 |
– accumulated amortisation and impairment |  | (2,265 | ) |  | (149 | ) |  | (1,250 | ) |  | (1,074 | ) |  | (4,738 | )
|  |  |  | Trademarks, |  | Contract |  |  |  |  |  |  |
| Exploration |  | patented and |  | based |  | Other |  |  |  |
| and |  | non-patented |  | intangible |  | intangible |  |  |  |
| evaluation (a) |  | technology |  | assets (b) |  | assets |  | Total |
Year ended 31 December 2016 | US$m |  | US$m |  | US$m |  | US$m |  | US$m |
Net book value |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
At 1 January 2016 |  | 706 |  |  | 94 |  |  | 2,138 |  |  | 398 |  |  | 3,336 |
Adjustment on currency translation |  | 14 |  |  | (3 | ) |  | 47 |  |  | - |  |  | 58 |
Expenditure during the year |  | 8 |  |  | - |  |  | - |  |  | 23 |  |  | 31 |
Amortisation for the year (c) |  | - |  |  | (13 | ) |  | (87 | ) |  | (127 | ) |  | (227 | )
Impairment charges (d) |  | - |  |  | - |  |  | - |  |  | (1 | ) |  | (1 | )
Disposals, transfers and other movements (e) |  | (17 | ) |  | - |  |  | 5 |  |  | 94 |  |  | 82 |
At 31 December 2016 |  | 711 |  |  | 78 |  |  | 2,103 |  |  | 387 |  |  | 3,279 |
– cost |  | 2,588 |  |  | 199 |  |  | 3,897 |  |  | 1,329 |  |  | 8,013 |
– accumulated amortisation and impairment |  | (1,877 | ) |  | (121 | ) |  | (1,794 | ) |  | (942 | ) |  | (4,734 | )
(a) | Exploration and evaluation assets’ useful lives are not determined until transferred to property, plant and equipment.
(b) | The Group benefits from certain intangible assets acquired with Alcan, including power supply contracts, customer contracts and water rights. The water rights are expected to contribute to the efficiency and cost effectiveness of operations for the foreseeable future: accordingly, these rights are considered to have indefinite lives and are not subject to amortisation but are tested annually for impairment. These water rights constitute the majority of the amounts in “Contract based intangible assets”.
The remaining carrying value of the water rights (US$1,824 million) as at 31 December 2017 relates wholly to the Quebec smelters cash-generating unit. The Quebec smelters cash-generating unit was tested for impairment by reference to FVLCD using discounted cash flows, which is in line with the policy set out in note 1(i). The recoverable amount of the Quebec smelters is classified as level 3 under the fair value hierarchy. In arriving at FVLCD, post-tax cash flows expressed in real terms have been estimated over the expected useful economic lives of the underlying smelting assets and discounted using a real post-tax discount rate of 6.7 per cent (2016: 7.0 per cent). The recoverable amounts were determined to be significantly in excess of carrying value, and there are no reasonably possible changes in key assumptions that would cause the remaining water rights to be impaired.
(c) | Finite life intangible assets are amortised over their useful economic lives on a straight-line or units of production basis, as appropriate. Where amortisation is calculated on a straight-line basis, the following useful lives have been determined:
Trademarks, patented and non-patented technology Trademarks: 14 to 20 years Patented and non-patented technology: ten to 20 years Contract-based intangible assets Power contracts / water rights: two to 45 years Other purchase and customer contracts: five to 15 years Other intangible assets Internally generated intangible assets and computer software: two to five years Other intangible assets: two to 20 years
(d) | Impairment charges in 2017 relate to the full write-off of the Roughrider deposit in Canada (see note 6). Impairment charges in 2016 related to the full write-off of the intangible assets of the Argyle cash-generating unit (see note 6).
(e) | Disposals, transfers and other movements for Exploration and Evaluation includes US$34 million transferred to Mining Property in relation to the Kemano tunnel project following approval of the project. Disposals, transfers and other movements for exploration and evaluation in 2016 included the disposal of the Mount Pleasant thermal coal project in New South Wales, Australia.
Summary of exploration and evaluation expenditure | The charge for the year and the net amount of intangible assets capitalised during the year are as follows:
|  |  |  | 2017 |  |  | 2016 |  |  | 2015 |
|  |  | US$m |  | US$m |  | US$m |
Net expenditure in the year (net of proceeds of US$3 million (2016: US$208 million; 2015: US$nil) on disposal of undeveloped projects) |  |  |  | (493 | ) |  | (284 | ) |  | (705 | )
Non-cash movements and non-cash proceeds on disposal of undeveloped projects |  |  |  | (24 | ) |  | (177 | ) |  | (15 | )
Amount capitalised during the year |  |  |  | 57 |  |  | 8 |  |  | 152 |
Net charge for the year |  |  |  | (460 | ) |  | (453 | ) |  | (568 | )
Reconciliation to income statement |  |  |  |  |  |  |  |  |  |  |
Exploration and evaluation costs |  |  |  | (445 | ) |  | (497 | ) |  | (576 | )
Profit relating to interests in undeveloped projects |  |  |  | (15 | ) |  | 44 |  |  | 8 |
Net charge for the year |  |  |  | (460 | ) |  | (453 | ) |  | (568 | )

X
- Definition The disclosure of detailed information about intangible assets. [Refer: Intangible assets other than goodwill] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 38 -IssueDate 2016-01-13 -Paragraph 118 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=38&date=2016-03-30&anchor=para_118&doctype=Standard -URIDate 2016-03-31 + Details
Name: | ifrs-full_DisclosureOfDetailedInformationAboutIntangibleAssetsExplanatory
Namespace Prefix: | ifrs-full_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition The entire disclosure for exploration and evaluation assets. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 6 -IssueDate 2016-01-13 -Section Disclosure -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=6&date=2016-03-30&anchor=sect_Disclosure&doctype=Standard -URIDate 2016-03-31 + Details
Name: | ifrs-full_DisclosureOfExplorationAndEvaluationAssetsExplanatory
Namespace Prefix: | ifrs-full_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

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