Retirement Plan And Other Post-Retirement Benefits (Narrative) (Details) $ in Millions	9 Months Ended
	Jun. 30, 2020 USD ($)
Retirement Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Company's contributions	$ 23.5
VEBA Trusts [Member]
Defined Benefit Plan Disclosure [Line Items]
Company's contributions	2.7
Estimated future contributions in remainder of fiscal year	0.2
Minimum [Member] | Retirement Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Estimated future contributions in remainder of fiscal year	1.0
Maximum [Member] | Retirement Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Estimated future contributions in remainder of fiscal year	$ 6.0