Fair Value Measurements - Schedule of Carrying Amounts and Estimated Fair Values of Financial Instruments not Recorded at Fair Value in the Financial Statements (Details) - Level 2 - USD ($) $ in Millions	Mar. 31, 2025	Jun. 30, 2024
Carrying Value
Carrying amounts and estimated fair values of financial instruments not recorded at fair value
Long-term debt	$ 695.1	$ 694.2
Company-owned life insurance	31.3	31.8
Fair Value
Carrying amounts and estimated fair values of financial instruments not recorded at fair value
Long-term debt	709.3	709.1
Company-owned life insurance	$ 31.3	$ 31.8