Basis of Presentation and Summary of Significant Accounting Policies (Narrative, Goodwill and Other Intangible Assets) (Details) - USD ($) $ in Millions	12 Months Ended
	Jun. 30, 2026	Jun. 30, 2025
Goodwill and Intangible Assets [Line Items]
Goodwill impairment loss	$ 184
GMPD
Goodwill and Intangible Assets [Line Items]
Goodwill impairment loss	$ 0	$ 675
Goodwill, Impairment Loss, Statement of Income or Comprehensive Income [Extensible Enumeration]	Operating Income (Loss)
Minimum
Goodwill and Intangible Assets [Line Items]
Discount Rate, fair value inputs	8.00%
Maximum
Goodwill and Intangible Assets [Line Items]
Discount Rate, fair value inputs	12.00%

Amount of impairment loss from asset representing future economic benefit arising from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized.