Employee Share Ownership Plans - Summary of Fair Value and Assumptions in the Calculation of Fair Value for Awards Issued (Detail) - 12 months ended Jun. 30, 2022	USD ($) yr $ / shares	USD ($) yr £ / shares
BHP Group Limited [member] \| CDP awards [Member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Weighted average fair value of awards granted during the year \| $	$ 27.46	$ 27.46
Share price at grant date \| $ / shares	$ 38.05
BHP Group Limited [member] \| CDP awards [Member] \| Bottom of range [member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Estimated life of awards \| yr	2	2
BHP Group Limited [member] \| CDP awards [Member] \| Top of range [member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Estimated life of awards \| yr	5	5
BHP Group Limited [member] \| LTIP awards [member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Weighted average fair value of awards granted during the year \| $	$ 13.66	$ 13.66
Risk-free interest rate	1.36%	1.36%
Estimated life of awards \| yr	5	5
Share price at grant date \| $ / shares	$ 38.05
Estimated volatility of share price	30.00%	30.00%
BHP Group Limited [member] \| MAP awards [member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Weighted average fair value of awards granted during the year \| $	$ 22.1	$ 22.1
BHP Group Limited [member] \| MAP awards [member] \| Bottom of range [member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Estimated life of awards \| yr	1	1
Dividend yield	5.00%	5.00%
BHP Group Limited [member] \| MAP awards [member] \| Top of range [member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Estimated life of awards \| yr	5	5
Dividend yield	7.50%	7.50%
BHP Group Limited [member] \| MAP awards [member] \| Range One [Member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Share price at grant date \| $ / shares	$ 51.33
BHP Group Limited [member] \| MAP awards [member] \| Range Two [Member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Share price at grant date \| $ / shares	36.39
BHP Group Limited [member] \| MAP awards [member] \| Range Three [Member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Share price at grant date \| $ / shares	46.55
BHP Group Limited [member] \| MAP awards [member] \| Range Four [Member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Share price at grant date \| $ / shares	50.58
BHP Group Limited [member] \| MAP awards [member] \| Range Five [Member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Share price at grant date \| $ / shares	$ 42.52
BHP Group Limited [member] \| Shareplus [member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Weighted average fair value of awards granted during the year \| $	$ 22.8	$ 22.8
Risk-free interest rate	0.12%	0.12%
Estimated life of awards \| yr	3	3
Share price at grant date \| $ / shares	$ 45.66
Dividend yield	5.51%	5.51%
BHP Group Plc [member] \| MAP awards [member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Weighted average fair value of awards granted during the year \| $	$ 20.85	$ 20.85
Estimated life of awards \| yr	3	3
Share price at grant date \| £ / shares		$ 18.62
BHP Group Plc [member] \| MAP awards [member] \| Bottom of range [member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Dividend yield	5.00%	5.00%
BHP Group Plc [member] \| MAP awards [member] \| Top of range [member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Dividend yield	7.50%	7.50%
BHP Group Plc [member] \| Shareplus [member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Weighted average fair value of awards granted during the year \| $	$ 14.53	$ 14.53
Risk-free interest rate	0.15%	0.15%
Estimated life of awards \| yr	3	3
Share price at grant date \| £ / shares		$ 20.68
Dividend yield	6.60%	6.60%

The expected volatility of the share price used to calculate the fair value of the share options granted. Expected volatility is a measure of the amount by which a price is expected to fluctuate during a period. The measure of volatility used in option pricing models is the annualised standard deviation of the continuously compounded rates of return on the share over a period of time.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
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-IssueDate 2021-01-01
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The option life of share options granted.

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The implied yield currently available on zero-coupon government issues of the country in whose currency the exercise price for share options granted is expressed, with a remaining term equal to the expected term of the option being valued (based on the option's remaining contractual life and taking into account the effects of expected early exercise). [Refer: Government [member]]

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Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table.

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The percentage of an expected dividend used to calculate the fair value of share options granted.

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The weighted average fair value of share options granted during the period at the measurement date. [Refer: Weighted average [member]]

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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The weighted average share price used as input to the option pricing model to calculate the fair value of share options granted. [Refer: Option pricing model [member]; Weighted average [member]]

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