Income Taxes - Unrecognized Tax Benefits - Interest Expense (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Jun. 30, 2021	Jun. 30, 2021
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense [Abstract]
Interest related to unrecognized benefits	$ 0.1	$ 0.1

Amount of interest expense for an underpayment of income taxes.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=121826272&loc=d3e32718-109319

Name:	us-gaap_UnrecognizedTaxBenefitsInterestOnIncomeTaxesExpense
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration