Other Balance Sheet Components - Accounts Receivable, Net (Details) - USD ($) $ in Thousands |
12 Months Ended | ||
|---|---|---|---|
Sep. 30, 2024 |
Sep. 30, 2023 |
Sep. 30, 2022 |
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| Accounts, Notes, Loans and Financing Receivable [Line Items] | |||
| Allowance for credit losses | $ (4,791) | $ (3,719) | |
| Accounts receivable, net | 879,514 | 826,873 | |
| Accounts Receivable, Allowance for Credit Loss [Roll Forward] | |||
| Balance at beginning of period | 3,719 | 8,273 | $ 8,044 |
| Provision for estimated credit losses | 12,761 | 7,097 | 6,799 |
| Write-offs, net of recoveries | (11,689) | (11,651) | (6,570) |
| Balance at end of period | 4,791 | 3,719 | $ 8,273 |
| Billed and billable receivables | |||
| Accounts, Notes, Loans and Financing Receivable [Line Items] | |||
| Accounts Receivable Gross | 734,817 | 692,707 | |
| Unbilled receivables | |||
| Accounts, Notes, Loans and Financing Receivable [Line Items] | |||
| Accounts Receivable Gross | $ 149,488 | $ 137,885 | |
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount, before allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of allowance for credit loss on accounts receivable. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of allowance for credit loss on accounts receivable, classified as current. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of increase in allowance for credit loss on accounts receivable, from recovery. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
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- Definition Amount of direct write-downs of accounts receivable charged against the allowance. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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