Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as noncurrent.

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Amount of unrealized gain on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Amount of investment in equity security without readily determinable fair value.

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The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

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Investments (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
Investments (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Schedule of Equity Method Investments [Line Items]
Gain on interest in investment	$ 16,090	$ 0	$ 36,281	$ 0
Mastery Logistics Systems, Inc.
Schedule of Equity Method Investments [Line Items]
Initial value of ownership interest in investment	$ 10,000		$ 10,000		$ 5,000
Ownership interest in investment	9.80%		9.80%
Gain on interest in investment	$ 28,200
Fair value of investment	38,200		$ 38,200		5,000
TuSimple
Schedule of Equity Method Investments [Line Items]
Initial value of ownership interest in investment	5,000		5,000		0
Gain on interest in investment			8,100
Loss on interest in investment	12,100
Fair value of investment	$ 13,100		$ 13,100		$ 0