Income Taxes - Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Reconciliation between the amount of reported income tax and the amount computed using U.S. Statutory rate
Pre-Tax Loss	$ (50,878)	$ (151,949)	$ (117,313)
Loss at Statutory Rates	(10,684)	(31,909)	(39,887)
Difference in Foreign Tax Rates			326
Research and Development Credits	(1,902)	(2,056)	(2,847)
State Taxes	(2,170)	(6,406)	(6,283)
Income Tax Rate Change			99,528
Other	(1,011)	(1,175)	(321)
Change in Fair Value Remeasurement of Contingent Consideration	(272)	(6,220)
Intangible Impairment		19,105
Recognition of APIC NOLs			(5,729)
Impact of Pass-through Entities		(913)	(2,775)
Expiration of NOLs and R&D Credit	18,966
Change in Valuation Allowance	$ (2,927)	28,809	(66,294)
Income Tax (Benefit) Provision		$ (765)	$ (24,282)

Amount represents income tax reconciliation of change in fair value remeasurement of contingent consideration.

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The portion of the difference between total income tax expense or benefit as reported in the Income Statement and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to expiration of net operating losses and research and development tax credits under enacted tax laws during the period.

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Amount represents income tax reconciliation impact of pass through entities.

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Amount represents income tax reconciliation of additional paid in capital and net operating losses.

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

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Amount 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 increase (decrease) in the valuation allowance for deferred tax assets.

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Amount 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 increase (decrease) in the income tax rates.

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