Share-Based Compensation Narrative (Details) shares in Millions, $ in Millions	3 Months Ended
Sep. 30, 2026 USD ($) Reportable_Segments shares	Sep. 30, 2025 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Tax benefit related to share-based compensation	$ 5.0	$ 4.0
Restricted Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)	3 years
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount	$ 120.0
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition	2 years
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Vested	$ 52.0	53.0
Performance Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount	$ 63.0
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition	2 years
Vesting Period in years for Shares \| Reportable_Segments	3
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Vested	$ 110.0	108.0
GIA Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount	$ 372.0
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition	4 years
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Vested	$ 46.0	53.0
Share-Based Payment Arrangement, Expense, Increase in Fair Value of Liabilities	$ 34.0	$ 10.0
2021 LTIP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant \| shares	16

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