Goodwill and intangible assets - Narrative (Details) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Sep. 30, 2022 |
Sep. 30, 2021 |
Sep. 30, 2020 |
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| Goodwill and Intangible Assets Disclosure [Abstract] | |||
| Increase (decrease) in goodwill | $ 63.4 | $ 21.3 | |
| Increase (decrease) in intangible assets | 46.5 | 18.4 | |
| Total amortization expense related to intangible assets | $ 4.9 | $ 0.5 | $ 0.2 |
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- Definition The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of increase (decrease) in carrying value of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. No definition available.
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- References No definition available.
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- Definition Amount of increase (decrease) 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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