Stockholders' Equity - Schedule of Other Comprehensive (Loss) Income (Details) - USD ($) $ in Millions	12 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2024
Other comprehensive income (loss), net of tax:
Other comprehensive income (loss), net of tax	$ 17	$ (17)	$ 42
AOCI Attributable to Parent
Before tax
Other comprehensive (loss) income	25	(25)	55
Tax benefit (provision)
Other comprehensive (loss) income	(8)	8	(13)
Other comprehensive income (loss), net of tax:
Other comprehensive income (loss), net of tax	17	(17)	42
Accumulated Defined Benefit Plans Adjustment Attributable to Parent
Before tax
Unrealized (loss) gains	19	(32)	47
Reclassifications realized in net income	6	1	8
Tax benefit (provision)
Unrealized (loss) gains	(5)	8	(11)
Reclassifications realized in net income	(3)	0	(2)
Other comprehensive income (loss), net of tax:
Unrealized (loss) gains	14	(24)	36
Reclassifications realized in net income	$ 3	1	$ 6
Accumulated Foreign Currency Adjustment Attributable to Parent
Before tax
Cumulative translation adjustment		6
Tax benefit (provision)
Cumulative translation adjustment		0
Other comprehensive income (loss), net of tax:
Cumulative translation adjustment		$ 6