Segment and Geographic Information - Summary of Revenue and Profit Attributable to Our Operating Segments (Parenthetical) (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Segment Reporting Revenue Reconciling Item [Line Items]
Depreciation and amortization	$ 87,694	$ 85,239	$ 80,817
Unallocated
Segment Reporting Revenue Reconciling Item [Line Items]
Depreciation and amortization	21,400	21,000	19,400
Software Products \| Operating Segments
Segment Reporting Revenue Reconciling Item [Line Items]
Depreciation and amortization	4,900	4,000	4,200
Professional Services \| Operating Segments
Segment Reporting Revenue Reconciling Item [Line Items]
Depreciation and amortization	$ 900	$ 1,100	$ 1,100

The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 22
-Subparagraph (e)
-URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e8736-108599

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3602-108585

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