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Subsequent Events (Details) - USD ($) $ in Thousands |  | 3 Months Ended | 6 Months Ended
--- | --- | --- | ---
Jul. 01, 2021 | Jun. 30, 2021 | Jun. 30, 2020 | Jun. 30, 2021 | Jun. 30, 2020
Subsequent Event [Line Items] |  |  |  |  |
Gain on equity investment |  | $ 20,191 | $ 0 | $ 20,191 | $ 0
TuSimple |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |
Gain on equity investment |  | 20,191 |  | 20,191 |
Fair value of investment |  | $ 25,191 |  | $ 25,191 |
Acquisition of ECM Transport Group [Member] |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |
Cash purchase price of ECM | $ 142,400 |  |  |  |
Percentage of equity interests acquired | 80.00% |  |  |  |

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- Definition Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event. + References No definition available. + Details
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