Stockholders' Equity - Schedule of Components of Accumulated Other Comprehensive (Loss) Income, Net of Tax (Details) - USD ($) $ in Millions	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2024
Equity [Abstract]
Benefit plan adjustments and other	$ (109)	$ (126)	$ (103)
Cumulative translation adjustment	2	2	(4)
Accumulated other comprehensive loss, net of tax	$ (107)	$ (124)	$ (107)

Amount, after tax, of accumulated increase (decrease) in equity from transaction and other event and circumstance from nonowner source.

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+ Details