Debt - Schedule of Long-term Debt Outstanding (Details) - USD ($) $ in Millions	Jun. 30, 2025	Jun. 30, 2024
Revolving Credit Agreement
Aggregate maturities of long-term debt	$ 300.0	$ 300.0
Long-term debt, net of current portion	$ 695.4	$ 694.2
Senior unsecured notes, 7.625% due March 2030 (face value of $300.0 million at June 30, 2025 and 2024)
Revolving Credit Agreement
Interest rate	7.625%	7.625%
Total debt	$ 297.5	$ 297.0
Senior Notes
Revolving Credit Agreement
Total debt	695.4	694.2
Less: amounts due within one year	0.0	0.0
Long-term debt, net of current portion	$ 695.4	$ 694.2
Senior Notes \| Senior unsecured notes, 6.375% due July 2028 (face value of $400.0 million at June 30, 2025 and 2024)
Revolving Credit Agreement
Interest rate	6.375%	6.375%
Face amount	$ 400.0	$ 400.0
Total debt	$ 397.9	$ 397.2

Face (par) amount of debt instrument at time of issuance.

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Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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