Organization and Basis of Presentation - Narrative (Details) $ in Thousands |
9 Months Ended | ||
|---|---|---|---|
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Jun. 30, 2020
USD ($)
segment
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Oct. 01, 2019
USD ($)
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Sep. 30, 2019
USD ($)
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| New Accounting Pronouncements or Change in Accounting Principle [Line Items] | |||
| Goodwill | $ 586,757 | $ 584,469 | |
| Number of operating segments | segment | 3 | ||
| Billed, billable and unbilled accounts receivable | $ 829,700 | ||
| Bad debt expense | 8,800 | ||
| Total lease liabilities | $ 178,114 | ||
| Accounting Standards Update 2016-02 | |||
| New Accounting Pronouncements or Change in Accounting Principle [Line Items] | |||
| Total lease liabilities | $ 214,500 |
| X | ||||||||||
- Definition Amount of increase (decrease) in allowance for credit loss on accounts receivable. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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. No definition available.
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- Definition Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Present value of lessee's discounted obligation for lease payments from operating lease. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The total amount due to the entity within one year of the balance sheet date (or one operating cycle, if longer) from outside sources, including trade accounts receivable, notes and loans receivable, as well as any other types of receivables, net of allowances established for the purpose of reducing such receivables to an amount that approximates their net realizable value. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Details
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