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Revenue (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2021 | Sep. 30, 2020 | Sep. 30, 2021 | Sep. 30, 2020
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 1,866,352 | $ 701,729 | $ 3,595,705 | $ 2,037,059
Clients 1-5 |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 525,806 | 269,460 | 1,242,446 | 802,503
Clients 6-10 |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 283,003 | 89,062 | 472,788 | 249,807
Clients 11-25 |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 398,816 | 118,156 | 704,312 | 344,463
Other |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 658,727 | $ 225,051 | $ 1,176,159 | $ 640,286
Customer A | Customer concentration risk | Revenue benchmark |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Customer concentration risk |  | 12.40% |  | 11.50%
Customer B | Customer concentration risk | Revenue benchmark |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Customer concentration risk |  |  |  | 10.70%

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