INCOME TAXES - Reconciliation between the effective tax rate and the statutory tax rate (Details)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Federal statutory rate	21.00%	21.00%	34.00%
State statutory rate, net of federal benefit	(0.70%)	0.90%	0.80%
Effect of foreign rates different from statutory	0.00%	0.20%	(0.20%)
Change in state rate	(1.30%)	(1.20%)	3.80%
Change in federal rate (34% to 21%)	0.00%	0.00%	(9.80%)
Nondeductible/nontaxable items	0.30%	4.90%	(122.20%)
Change in valuation allowance	(19.30%)	(25.80%)	93.60%
Income tax expense (benefit)	0.00%	0.00%	0.00%

Effective Income Tax Rate Reconciliation, Change In Enacted State Tax Rate, Percent

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to changes in the valuation allowance for deferred tax assets.

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations applicable to statutory income tax expense (benefit) outside of the country of domicile.

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations applicable to state and local income tax expense (benefit), net of federal tax expense (benefit).

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