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v3.22.1

Revenue from Contracts with Clients - Narrative (Details) | 3 Months Ended | 6 Months Ended
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Mar. 31, 2022 | Mar. 31, 2021 | Mar. 31, 2022 | Mar. 31, 2021
Revenue from Contract with Customer [Abstract] |  |  |  |
Total revenues (percentage) | 5.90% | 5.00% | 6.20% | 4.00%

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