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Acquisitions - Additional Information (Detail) - USD ($) $ in Millions |  |  | 6 Months Ended | 12 Months Ended
--- | --- | --- | --- | ---
Mar. 06, 2020 | Jan. 31, 2019 | Jun. 30, 2020 | Dec. 31, 2019
Business Acquisition [Line Items] |  |  |  |
Total consideration transferred |  |  | $ 9.6 | $ 102.8
Goodwill acquired during period net of assets acquired |  |  | 3.0 | $ 48.7
Measurement period adjustments |  |  | $ 0.1 |
Ed Broking [Member] |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Business acquisition date |  | Jan. 31, 2019 |  |
Algomi Limited [Member] |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Business acquisition date | Mar. 06, 2020 |  |  |

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