INCOME TAXES - Income Tax Reconciliation (Details)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Statutory U.S. federal tax rate	21.00%	21.00%	35.00%
State taxes, net of federal benefit	2.60%	4.70%	3.30%
Impact of 2017 tax reform on deferred tax balance	0.00%	0.00%	4.50%
Equity-based compensation expense	(0.40%)	(1.50%)	(0.80%)
Contingent consideration	0.00%	7.10%	4.40%
In-process research and development	(3.40%)	0.00%	0.00%
Other permanent items, net	(0.40%)	(1.40%)	(0.50%)
Tax credits	0.40%	6.20%	0.70%
Valuation allowance	(19.80%)	(67.40%)	(0.80%)
Other, net	0.00%	0.60%	0.10%
Effective tax rate	0.00%	(30.70%)	45.90%

Effective Income Tax Rate Reconciliation, Nondeductible Expense, Contingent Consideration, 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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-Publisher FASB
-Name Accounting Standards Codification
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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 difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to nondeductible expense for share-based payment arrangement.

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Percentage of the difference, between reported income tax expense (benefit) and the expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations, that is attributable to tax exempt income, equity in earnings (loss) of an unconsolidated subsidiary, minority interest income (expense), tax holiday, disposition of a business, disposition of an asset, repatriation of foreign earnings, repatriation of foreign earnings jobs creation act of 2004, change in enacted tax rate, prior year income taxes, change in deferred tax asset valuation allowance, and other adjustments.

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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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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 tax credits. Including, but not limited to, research credit, foreign tax credit, investment tax credit, and other tax credits.

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