Amount of loss contingency liability.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=121557415&loc=d3e14326-108349

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

Contingencies (Details)	Jul. 30, 2021 defendant	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)
Contingencies [Line Items]
Contingent liabilities \| $		$ 0	$ 0
Putative securities class action lawsuit \| Pending litigation \| Officer
Contingencies [Line Items]
Number of defendants \| defendant	2