Employee Benefit Plans (Investments of the Plan Measured at Fair Value) (Details) - USD ($) $ in Millions	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2021
Defined Benefit Plan Disclosure [Line Items]
Plan assets	$ 1,854.4	$ 1,800.5	$ 2,306.3
Commingled trusts
Defined Benefit Plan Disclosure [Line Items]
Plan assets	829.5	798.2
Commingled trusts | Level 1
Defined Benefit Plan Disclosure [Line Items]
Plan assets	0.0	0.0
Commingled trusts | Level 2
Defined Benefit Plan Disclosure [Line Items]
Plan assets	829.5	798.2
Commingled trusts | Level 3
Defined Benefit Plan Disclosure [Line Items]
Plan assets	0.0	0.0
U.S. government securities
Defined Benefit Plan Disclosure [Line Items]
Plan assets	351.7	350.7
U.S. government securities | Level 1
Defined Benefit Plan Disclosure [Line Items]
Plan assets	0.0	0.0
U.S. government securities | Level 2
Defined Benefit Plan Disclosure [Line Items]
Plan assets	351.7	350.7
U.S. government securities | Level 3
Defined Benefit Plan Disclosure [Line Items]
Plan assets	0.0	0.0
Mutual funds
Defined Benefit Plan Disclosure [Line Items]
Plan assets	297.2	263.6
Mutual funds | Level 1
Defined Benefit Plan Disclosure [Line Items]
Plan assets	18.2	11.0
Mutual funds | Level 2
Defined Benefit Plan Disclosure [Line Items]
Plan assets	279.0	252.6
Mutual funds | Level 3
Defined Benefit Plan Disclosure [Line Items]
Plan assets	0.0	0.0
Corporate and municipal bonds
Defined Benefit Plan Disclosure [Line Items]
Plan assets	355.1	322.4
Corporate and municipal bonds | Level 1
Defined Benefit Plan Disclosure [Line Items]
Plan assets	0.0	0.0
Corporate and municipal bonds | Level 2
Defined Benefit Plan Disclosure [Line Items]
Plan assets	355.1	322.4
Corporate and municipal bonds | Level 3
Defined Benefit Plan Disclosure [Line Items]
Plan assets	0.0	0.0
Mortgage-backed security bonds
Defined Benefit Plan Disclosure [Line Items]
Plan assets	18.7	32.8
Mortgage-backed security bonds | Level 1
Defined Benefit Plan Disclosure [Line Items]
Plan assets	0.0	0.0
Mortgage-backed security bonds | Level 2
Defined Benefit Plan Disclosure [Line Items]
Plan assets	18.7	32.8
Mortgage-backed security bonds | Level 3
Defined Benefit Plan Disclosure [Line Items]
Plan assets	0.0	0.0
Total pension asset investments
Defined Benefit Plan Disclosure [Line Items]
Plan assets	1,852.2	1,767.7
Total pension asset investments | Level 1
Defined Benefit Plan Disclosure [Line Items]
Plan assets	18.2	11.0
Total pension asset investments | Level 2
Defined Benefit Plan Disclosure [Line Items]
Plan assets	1,834.0	1,756.7
Total pension asset investments | Level 3
Defined Benefit Plan Disclosure [Line Items]
Plan assets	$ 0.0	$ 0.0