Fair Value Measurements - Narrative (Details) - USD ($) $ in Billions	Mar. 31, 2023	Sep. 30, 2022
Fair Value [Line Items]
Fair value of long term debt	$ 8.1	$ 7.3
Quoted Prices in Active Markets (Level 1)
Fair Value [Line Items]
Fair value of long term debt	7.7	7.1
Significant Other Observable Inputs (Level 2)
Fair Value [Line Items]
Fair value of long term debt	$ 0.4	$ 0.2

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://www.xbrl.org/2003/role/exampleRef
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Name:	us-gaap_DebtInstrumentFairValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant