Organization and Summary of Significant Accounting Policies - Foreign Currency and Advertising (Details) - USD ($) $ in Millions	12 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Foreign currency transaction gains (losses) not accounted for as translations	$ 0.0	$ 0.1	$ 0.5
Advertising expense	$ 2.3	$ 1.6	$ 2.0

Amount before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
-SubTopic 20
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=125521441&loc=d3e30690-110894

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
-SubTopic 20
-Section 35
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=123602790&loc=d3e30226-110892

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
-SubTopic 10
-Section 45
-Paragraph 17
-URI https://asc.fasb.org/extlink&oid=126980362&loc=d3e28228-110885

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
-SubTopic 20
-Section 50
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=124440516&loc=d3e30840-110895

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