New Accounting Guidance	12 Months Ended
	Sep. 30, 2021
Accounting Changes and Error Corrections [Abstract]
New Accounting Guidance	New Accounting Guidance Recently Adopted Accounting GuidanceOn October 1, 2020, the Company adopted new guidance issued by the Financial Accounting Standards Board (“FASB”) for credit losses. The new guidance requires the application of a current expected credit loss model for financial assets measured at amortized cost, including receivables, and an allowance for credit loss model for available-for-sale debt securities. The Company adopted the new guidance using the modified retrospective approach and recognized a cumulative effect adjustment resulting in a decrease of $4.1 million in receivables, net, offset by decreases of $0.8 million in deferred tax liabilities and $3.3 million in retained earnings as of October 1, 2020