Business combinations and disposal Business combinations and disposals - Ascend Management Innovations, LLC (Details) - USD ($) $ in Thousands |
12 Months Ended | |||
|---|---|---|---|---|
Feb. 29, 2016 |
Sep. 30, 2018 |
Sep. 30, 2017 |
Sep. 30, 2016 |
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| Business Acquisition [Line Items] | ||||
| Goodwill | $ 399,882 | $ 402,976 | $ 397,558 | |
| Ascend Management Innovations LLC | ||||
| Business Acquisition [Line Items] | ||||
| Share capital acquired (as a percent) | 100.00% | |||
| Purchase consideration, net of cash acquired | $ 44,100 | 44,069 | ||
| Intangible assets | $ 22,300 | 22,300 | ||
| Amortization period of intangible assets | 18 years | |||
| Goodwill | $ 18,000 | $ 17,997 |
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- Definition Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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 Percentage of voting equity interests acquired at the acquisition date in the business combination. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The amount of identifiable intangible assets recognized as of the acquisition date. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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://fasb.org/us-gaap/role/ref/legacyRef
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- Details
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