Discontinued Operations - Summary of Income Statement - Discontinued Operations (Detail) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
Jun. 30, 2019	Jun. 30, 2018
Disclosure of analysis of single amount of discontinued operations [abstract]
Profit/(loss) after taxation from operating activities	$ 175	$ (2,921)
Net loss on disposal	(510)
Loss after taxation	(335)	(2,921)
Attributable to non-controlling interests	7	26
Attributable to BHP shareholders	$ (342)	$ (2,947)
Basic loss per ordinary share (cents)	$ (0.066)	$ (0.554)
Diluted loss per ordinary share (cents)	$ (0.066)	$ (0.554)

Gain/(loss) after taxation from operating activities of discontinued operations.

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Basic earnings (loss) per share from discontinued operations. [Refer: Basic earnings (loss) per share; Discontinued operations [member]]

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Diluted earnings (loss) per share from discontinued operations. [Refer: Diluted earnings (loss) per share; Discontinued operations [member]]

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The gain (loss) recognised on the measurement to fair value less costs to sell or on the disposal of the assets or disposal group(s) constituting the discontinued operation. [Refer: Discontinued operations [member]]

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The profit (loss) from discontinued operations. [Refer: Discontinued operations [member]; Profit (loss)]

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The profit (loss) from discontinued operations attributable to non-controlling interests. [Refer: Profit (loss) from discontinued operations; Non-controlling interests]

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The profit (loss) from discontinued operations attributable to ordinary equity holders of the parent entity. [Refer: Profit (loss) from discontinued operations]

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