Discontinued Operations - Summary of Significant Non-Cash Items and Purchases of Property, Plant and Equipment on Cash Flows (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019
Adjustments to reconcile net loss to net cash used in operating activities
Depreciation and amortization	$ 9,593	$ 12,690
Unrealized and realized (appreciation) depreciation on equity securities and preferred stock, net	106	(5,702)
Equity in net loss of EnviroFlight	640	3,387
Stock-based compensation expense	9,269	9,115
Deferred income taxes	(136)	(981)
Gain on sale of discontinued operations	(672)	0
Loss on release of cumulative foreign currency translation adjustment	26,957	0
Cash flows from investing activities
Purchases of property, plant and equipment	(5,034)	(25,423)
TS Biotechnology Holdings LLC and EnviroFlight LLC \| Discontinued Operations, Held-for-sale
Adjustments to reconcile net loss to net cash used in operating activities
Depreciation and amortization	0	2,483
Unrealized and realized (appreciation) depreciation on equity securities and preferred stock, net	106	507
Equity in net loss of EnviroFlight	38	1,923
Stock-based compensation expense	(1,346)	1,351
Deferred income taxes	0	(935)
Gain on sale of discontinued operations	(672)	0
Loss on release of cumulative foreign currency translation adjustment	26,957	0
Cash flows from investing activities
Purchases of property, plant and equipment	$ (382)	$ (18,275)

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Amount of deferred income tax expense (benefit) pertaining to income (loss) from continuing operations.

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