Share-based Compensation - Changes in Restricted Shares/Units, Performance Rights/Units and Shares Rights (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2024
Restricted share units
Number
Outstanding at beginning of period (in shares)	0.5
Granted (in shares)	1.1
Exercised (in shares)	(0.3)
Forfeited (in shares)	(0.1)
Outstanding at end of period (in shares)	1.2	0.5
Weighted-average Grant Date Fair Value
Outstanding at beginning of period (in dollars per share)	$ 50.01
Granted (in dollars per share)	41.49	$ 52.98	$ 47.21
Exercised (in dollars per share)	48.07
Forfeited (in dollars per share)	42.53
Outstanding at end of period (in dollars per share)	$ 41.93	$ 50.01
Fair value vested ($ in millions)	$ 18	$ 8	$ 6
Performance rights/shares
Number
Outstanding at beginning of period (in shares)	2.4
Granted (in shares)	2.8
Exercised (in shares)	0.0
Forfeited (in shares)	(1.1)
Outstanding at end of period (in shares)	4.1	2.4
Weighted-average Grant Date Fair Value
Outstanding at beginning of period (in dollars per share)	$ 37.63
Granted (in dollars per share)	33.69	$ 41.60	$ 31.85
Exercised (in dollars per share)	37.34
Forfeited (in dollars per share)	38.51
Outstanding at end of period (in dollars per share)	$ 34.62	$ 37.63
Fair value vested ($ in millions)	$ 0	$ 25	$ 14
Share rights
Number
Outstanding at beginning of period (in shares)	3.4
Granted (in shares)	0.3
Exercised (in shares)	(1.6)
Forfeited (in shares)	(0.1)
Outstanding at end of period (in shares)	2.0	3.4
Weighted-average Grant Date Fair Value
Outstanding at beginning of period (in dollars per share)	$ 46.70
Granted (in dollars per share)	36.50	$ 46.98	$ 42.10
Exercised (in dollars per share)	46.09
Forfeited (in dollars per share)	45.15
Outstanding at end of period (in dollars per share)	$ 45.81	$ 46.70
Fair value vested ($ in millions)	$ 74	$ 15	$ 24

Fair Value of Shares Vested

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
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-Section 50
-Paragraph 2
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-Publisher FASB
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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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- Definition

Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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- Definition

The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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- Definition

Net number of non-option equity instruments granted to participants.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(01)
-SubTopic 10
-Topic 718
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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