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Borrowings - Schedule of Outstanding Borrowings (Details) - USD ($) $ in Millions	Mar. 31, 2025	Jun. 30, 2024	Aug. 17, 2023	May 31, 2021	Dec. 31, 2019	Jun. 30, 2016
Debt Instrument [Line Items]
Principal amount	$ 3,445.8
Long-term debt	3,433.6	$ 3,355.1
Unused Available Capacity	1,374.2
Fair value	3,258.9
Total debt	3,433.6	3,355.1
Revolving Credit Facility
Debt Instrument [Line Items]
Principal amount	125.8
Long-term debt	125.8	0.0
Unused Available Capacity	1,374.2
Fair value	125.8
Senior Notes
Debt Instrument [Line Items]
Principal amount	2,250.0
Long-term debt	2,239.1	2,237.2
Fair value	2,063.0
Fiscal 2025 Revolving Credit Facility U.S. Dollar Tranche \| Revolving Credit Facility
Debt Instrument [Line Items]
Principal amount	0.0
Long-term debt	0.0	0.0
Unused Available Capacity	1,000.0
Fair value	0.0
Fiscal 2025 Revolving Credit Facility Multicurrency Tranche \| Revolving Credit Facility
Debt Instrument [Line Items]
Principal amount	125.8
Long-term debt	125.8	0.0
Unused Available Capacity	374.2
Fair value	125.8
Fiscal 2024 Amended Term Loan \| Term Loans
Debt Instrument [Line Items]
Principal amount	1,070.0		$ 1,300.0
Long-term debt	1,068.7	1,117.9
Fair value	1,070.0
Fiscal 2016 Senior Notes \| Senior Notes
Debt Instrument [Line Items]
Principal amount	500.0					$ 500.0
Long-term debt	499.2	498.7
Fair value	493.2
Fiscal 2020 Senior Notes \| Senior Notes
Debt Instrument [Line Items]
Principal amount	750.0				$ 750.0
Long-term debt	745.8	745.1
Fair value	692.7	667.7
Fiscal 2021 Senior Notes \| Senior Notes
Debt Instrument [Line Items]
Principal amount	1,000.0			$ 1,000.0
Long-term debt	994.1	$ 993.4
Fair value	$ 877.2