Accounts Receivable Facility (Narrative) (Details) - Accounts receivable sales agreement - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Sep. 30, 2022
Transfer of Financial Assets Accounted for as Sales [Line Items]
Accounts receivable sold through AR Facility	$ 388.7	$ 354.0	$ 916.3	$ 791.2
Transfer of accounts receivable, sales amount derecognized	164.6		164.6		$ 78.7
Loss on sale of accounts receivable	$ 2.1	$ 0.6	$ 4.5	$ 1.1

Amount of derecognized financial assets from transactions which comprise an initial transfer and an agreement entered into in contemplation of the initial transfer resulting in retention of substantially all of the exposure to the economic return throughout the term of the transaction, at the date of derecognition.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 4D
-Subparagraph (a)
-SubTopic 20
-Topic 860
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481326/860-20-50-4D

Name:	us-gaap_TransferOfFinancialAssetsAccountedForAsSalesAmountDerecognized
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant