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Investments (Details) $ in Millions | Mar. 31, 2021 USD ($)
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Mastery Logistics System, Inc. |
Schedule of Equity Method Investments [Line Items] |
Value of ownership interest in investment | $ 5.0
Ownership interest in investment | 5.00%
TuSimple |
Schedule of Equity Method Investments [Line Items] |
Value of ownership interest in investment | $ 5.0

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