Commitments - Summary of Other Commitments (Detail) - USD ($) $ in Millions	Jun. 30, 2018	Jun. 30, 2017
Commitments under finance leases
Commitments under finance leases	$ 1,165	$ 1,315
Future financing liability	(363)	(418)
Right to reimbursement from joint operations partner	0	0
Finance lease liability	802	897
Commitments under operating leases
Commitments under operating leases	2,012	1,752
Due not later than one year [Member]
Commitments under finance leases
Commitments under finance leases	127	135
Commitments under operating leases
Commitments under operating leases	388	420
Due later than one year and not later than five years [member]
Commitments under finance leases
Commitments under finance leases	448	475
Commitments under operating leases
Commitments under operating leases	785	672
Due later than five years [member]
Commitments under finance leases
Commitments under finance leases	590	705
Commitments under operating leases
Commitments under operating leases	$ 839	$ 660

Obligations under finance lease [abstract]

No definition available.

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- Definition

Operating lease commitments abstract.

+ References

No definition available.

+ Details

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- Definition

The amount of liabilities related to finance leases.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Note Expiry date 2019-01-01
-Name IAS
-Number 1
-IssueDate 2017-01-01
-Paragraph 55
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-02&anchor=para_55&doctype=Standard&book=B
-URIDate 2017-03-09

+ Details

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- Definition

The amount representing the difference between the future minimum finance lease payments and their present value. Minimum lease payments are payments over the lease term that the lessee is or can be required to make, excluding contingent rent, costs for services and taxes to be paid by, and reimbursed to, the lessor, together with: (a) for a lessee, any amounts guaranteed by the lessee or by a party related to the lessee; or (b) for a lessor, any residual value guaranteed to the lessor by: (i) the lessee; (ii) a party related to the lessee; or (iii) a third party unrelated to the lessor that is financially capable of discharging the obligations under the guarantee.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Note Expiry date 2019-01-01
-Name IAS
-Number 17
-IssueDate 2017-01-01
-Paragraph 31
-Subparagraph b
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=17&date=2017-03-02&anchor=para_31_b&doctype=Standard&book=B
-URIDate 2017-03-09

+ Details

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- Definition

The amount of payments over the finance lease term that the lessee is or can be required to make, excluding contingent rent, costs for services and taxes to be paid by, and reimbursed to, the lessor, together with any amounts guaranteed by the lessee or by a party related to the lessee.

+ References

+ Details

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- Definition

The amount of future minimum lease payments payable under non-cancellable operating leases. Minimum lease payments are payments over the lease term that the lessee is or can be required to make, excluding contingent rent, costs for services and taxes to be paid by, and reimbursed to, the lessor, together with: (a) for a lessee, any amounts guaranteed by the lessee or by a party related to the lessee; or (b) for a lessor, any residual value guaranteed to the lessor by: (i) the lessee; (ii) a party related to the lessee; or (iii) a third party unrelated to the lessor that is financially capable of discharging the obligations under the guarantee.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Note Expiry date 2019-01-01
-Name IAS
-Number 17
-IssueDate 2017-01-01
-Paragraph 35
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=17&date=2017-03-02&anchor=para_35_a&doctype=Standard&book=B
-URIDate 2017-03-09

+ Details

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- Definition

The amount of undiscounted finance lease payments to be received. Finance lease is a lease that transfers substantially all the risks and rewards incidental to ownership of an underlying asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2019-01-01
-Name IFRS
-Number 16
-IssueDate 2017-01-01
-Paragraph 94
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=16&date=2017-03-01&anchor=para_94&doctype=Standard
-URIDate 2017-03-09

+ Details

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- Details

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- Details

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