Represents the California net operating loss carry over period

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Amount of federal net operating loss generated.

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Amount of federal operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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Amount of Federal research tax credit carryforwards

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Represents amount would impact the effective tax rate if adjustments are made after the valuation allowance is released

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Increase in Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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Tax Cuts and Jobs Act of 2017 limits a taxpayer's ability to utilize NOL carryforwards to 80% of taxable income and can be carried forward indefinitely (carryback is generally prohibited).

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Amount of federal and state operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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Amount of State research tax credit carryforwards

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Amount of current state and local tax expense (benefit) pertaining to income (loss) from continuing operations.

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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INCOME TAXES - Additional information (Details) - USD ($) $ in Thousands	9 Months Ended		12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
INCOME TAXES
Income before income taxes	$ (198,734)	$ (247,108)	$ (338,918)	$ (239,552)	$ (84,767)
State income tax expense			$ 252	$ 377
Federal statutory rates			21.00%	21.00%	34.00%
Valuation allowance			$ 174,863	$ 88,686
Increase in valuation allowance			86,200	55,000
Federal net operating loss ("NOL") carryforwards			630,400
State net operating loss ("NOL") carryforwards			$ 421,000
Percentage of taxable income utilize			80.00%
Federal NOLs generated			$ 347,500	$ 166,300
NOL Carry over period			20 years
Federal research tax credit carryforwards			$ 10,700
State research tax credit carryforwards			5,600
Impact on effective tax rate			$ 4,700