XML 179 R118.htm IDEA: XBRL DOCUMENT
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Share Capital - Summary of Share Capital (Parenthetical) (Detail) | 2 Months Ended | 12 Months Ended |  |  |
--- | --- | --- | --- | --- | ---
Sep. 07, 2018 shares | Jun. 30, 2018 $ / shares shares | Jun. 30, 2017 $ / shares shares | Jun. 30, 2016 $ / shares shares | Jun. 30, 2018 £ / shares | Jun. 30, 2017 £ / shares | Jun. 30, 2016 £ / shares
5.5% Preference shares [Member] |  |  |  |  |  |  |
Disclosure of classes of share capital [Line Items] |  |  |  |  |  |  |
Par value | £ / shares |  |  |  |  | £ 1 | £ 1 | £ 1
Dividend rate percentage |  | 5.50% | 5.50% | 5.50% |  |  |
BHP Billiton Limited [Member] |  |  |  |  |  |  |
Disclosure of classes of share capital [Line Items] |  |  |  |  |  |  |
Par value | $ / shares |  | $ 0.50 |  |  |  |  |
Number of ordinary shares issued on the exercise of awards |  | 7,339,522 | 6,945,570 | 6,846,091 |  |  |
BHP Billiton Limited [Member] | Major ordinary share transactions [Member] |  |  |  |  |  |  |
Disclosure of classes of share capital [Line Items] |  |  |  |  |  |  |
Number of ordinary shares issued on the exercise of awards | 0 |  |  |  |  |  |
BHP Billiton Plc [Member] |  |  |  |  |  |  |
Disclosure of classes of share capital [Line Items] |  |  |  |  |  |  |
Par value | $ / shares |  | $ 0.50 |  |  |  |  |
Number of ordinary shares issued on the exercise of awards |  | 711,705 | 940,070 | 966,473 |  |  |
BHP Billiton Plc [Member] | Major ordinary share transactions [Member] |  |  |  |  |  |  |
Disclosure of classes of share capital [Line Items] |  |  |  |  |  |  |
Number of ordinary shares issued on the exercise of awards | 0 |  |  |  |  |  |
BHP Billiton Plc [Member] | Special Voting share of par value [Member] |  |  |  |  |  |  |
Disclosure of classes of share capital [Line Items] |  |  |  |  |  |  |
Par value | $ / shares |  | $ 0.5 | $ 0.5 | $ 0.5 |  |  |
BHP Billiton Plc [Member] | 5.5% Preference shares [Member] |  |  |  |  |  |  |
Disclosure of classes of share capital [Line Items] |  |  |  |  |  |  |
Par value | £ / shares |  |  |  |  | £ 1 | £ 1 | £ 1
Dividend rate percentage |  | 5.50% | 5.50% | 5.50% |  |  |

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- Definition The nominal value per share. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2017-01-01 -Paragraph 79 -Subparagraph a -Clause iii -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_79_a_iii&doctype=Standard -URIDate 2017-03-09 + Details
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