For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 42
-URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e9054-108599

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
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-URI https://asc.fasb.org/extlink&oid=123594938&loc=d3e13531-108611

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
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-Subparagraph (a)
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Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI https://asc.fasb.org/extlink&oid=99393423&loc=d3e6404-108592

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Reportable Segment Information - Geographic Revenue and Long-lived Assets (Detail) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
U.S. [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets, net	$ 24,788	$ 25,920
Ireland [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets, net	$ 30,505	$ 41,224
Revenue [Member] \| Geographic Concentration Risk [Member] \| Domestic [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Percentage of consolidated revenue	74.00%	79.00%	78.00%
Revenue [Member] \| Geographic Concentration Risk [Member] \| Foreign [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Percentage of consolidated revenue	26.00%	21.00%	22.00%