Pension and Other Postretirement Benefits (Schedule of Weighted Average Asset Allocations by Asset Category) (Details) - Pension Benefits	Jun. 30, 2020	Jun. 30, 2019
Defined Benefit Plan Disclosure [Line Items]
Benefit plan weighted-average asset allocations percentage	100.00%	100.00%
Equity securities
Defined Benefit Plan Disclosure [Line Items]
Benefit plan weighted-average asset allocations percentage	51.00%	47.00%
Fixed income securities
Defined Benefit Plan Disclosure [Line Items]
Benefit plan weighted-average asset allocations percentage	21.00%	18.00%
Other, including cash
Defined Benefit Plan Disclosure [Line Items]
Benefit plan weighted-average asset allocations percentage	28.00%	35.00%