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Provisions, including post-retirement benefits - Summary of Provisions, including post-retirement benefits (Detail) - USD ($) $ in Millions | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2017 | Dec. 31, 2016
Disclosure of other provisions [Line Items] |  |  |  |  |
Provisions (including post-retirement benefits) at beginning balance | $ 13,794 | $ 13,066 |  |  |
Adjustment on currency translation | 846 | (56) |  |  |
Adjustments to mining properties |  |  |  |  |
– changes in estimate | 710 | (123) |  |  |
Charged/(credited) to profit: |  |  |  |  |
– increases to existing and new provisions | 797 | 1,630 |  |  |
– unused amounts reversed | (187) | (239) |  |  |
– exchange (gains)/losses on provisions | (83) | 13 |  |  |
– amortisation of discount | 383 | 338 | $ 378 |  |
Utilised in year | (1,053) | (997) |  |  |
Actuarial losses recognised in equity | 121 | 152 |  |  |
Subsidiaries no longer consolidated (d) | (622) | (63) |  |  |
Transfers to assets held for sale | (64) | (4) |  |  |
Transfers and other movements |  | 77 |  |  |
Provisions (including post-retirement benefits) at ending balance | 14,642 | 13,794 | 13,066 |  |
Balance sheet analysis: |  |  |  |  |
Current |  |  |  | $ 1,275 | $ 1,315
Non-current |  |  |  | 13,367 | 12,479
Total | 13,794 | 13,794 | $ 13,066 | 14,642 | 13,794
Pensions and post retirement healthcare [member] |  |  |  |  |
Disclosure of other provisions [Line Items] |  |  |  |  |
Provisions (including post-retirement benefits) at beginning balance | 3,167 |  |  |  |
Adjustment on currency translation | 200 |  |  |  |
Charged/(credited) to profit: |  |  |  |  |
– increases to existing and new provisions | 233 |  |  |  |
Utilised in year | (339) |  |  |  |
Actuarial losses recognised in equity | 121 |  |  |  |
Transfers to assets held for sale | (13) |  |  |  |
Transfers and other movements | 1 |  |  |  |
Provisions (including post-retirement benefits) at ending balance | 3,370 | 3,167 |  |  |
Balance sheet analysis: |  |  |  |  |
Current |  |  |  | 84 |
Non-current |  |  |  | 3,286 |
Total | 3,167 | 3,167 |  | 3,370 | 3,167
Other employee entitlements [member] |  |  |  |  |
Disclosure of other provisions [Line Items] |  |  |  |  |
Provisions (including post-retirement benefits) at beginning balance | 450 |  |  |  |
Adjustment on currency translation | 34 |  |  |  |
Charged/(credited) to profit: |  |  |  |  |
– increases to existing and new provisions | 96 |  |  |  |
– unused amounts reversed | (37) |  |  |  |
Utilised in year | (84) |  |  |  |
Subsidiaries no longer consolidated (d) | (69) |  |  |  |
Transfers to assets held for sale | (4) |  |  |  |
Transfers and other movements | 3 |  |  |  |
Provisions (including post-retirement benefits) at ending balance | 389 | 450 |  |  |
Balance sheet analysis: |  |  |  |  |
Current |  |  |  | 277 |
Non-current |  |  |  | 112 |
Total | 450 | 450 |  | 389 | 450
Close down and restoration/ environmental [member] |  |  |  |  |
Disclosure of other provisions [Line Items] |  |  |  |  |
Provisions (including post-retirement benefits) at beginning balance | 8,722 |  |  |  |
Adjustment on currency translation | 502 |  |  |  |
Adjustments to mining properties |  |  |  |  |
– changes in estimate | 710 |  |  |  |
Charged/(credited) to profit: |  |  |  |  |
– increases to existing and new provisions | 230 |  |  |  |
– unused amounts reversed | (61) |  |  |  |
– exchange (gains)/losses on provisions | (40) |  |  |  |
– amortisation of discount | 348 |  |  |  |
Utilised in year | (268) |  |  |  |
Subsidiaries no longer consolidated (d) | (102) |  |  |  |
Transfers to assets held for sale | (47) |  |  |  |
Transfers and other movements | (11) |  |  |  |
Provisions (including post-retirement benefits) at ending balance | 9,983 | 8,722 |  |  |
Balance sheet analysis: |  |  |  |  |
Current |  |  |  | 634 |
Non-current |  |  |  | 9,349 |
Total | 8,722 | 8,722 |  | 9,983 | 8,722
Other [member] |  |  |  |  |
Disclosure of other provisions [Line Items] |  |  |  |  |
Provisions (including post-retirement benefits) at beginning balance | 1,455 |  |  |  |
Adjustment on currency translation | 110 |  |  |  |
Charged/(credited) to profit: |  |  |  |  |
– increases to existing and new provisions | 238 |  |  |  |
– unused amounts reversed | (89) |  |  |  |
– exchange (gains)/losses on provisions | (43) |  |  |  |
– amortisation of discount | 35 |  |  |  |
Utilised in year | (362) |  |  |  |
Subsidiaries no longer consolidated (d) | (451) |  |  |  |
Transfers and other movements | 7 |  |  |  |
Provisions (including post-retirement benefits) at ending balance | 900 | 1,455 |  |  |
Balance sheet analysis: |  |  |  |  |
Current |  |  |  | 280 |
Non-current |  |  |  | 620 |
Total | $ 1,455 | $ 1,455 |  | $ 900 | $ 1,455

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- Definition The decrease in other provisions resulting from the loss of control of a subsidiary. [Refer: Other provisions] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 37 -IssueDate 2016-01-13 -Paragraph 84 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=37&date=2016-03-30&anchor=para_84&doctype=Standard -URIDate 2016-03-31 + Details
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