Income Taxes - Schedule of effective income tax rate reconciliation (Details)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Federal statutory tax rate	21.00%	21.00%
State taxes	(4.50%)	4.40%
Non deductible expenses	(0.30%)	(0.60%)
Tax credits	4.00%	4.60%
Expired tax credit	(1.30%)	(3.90%)
Deferred tax adjustment	(4.80%)	0.00%
Stock based compensation	1.90%	0.80%
Valuation allowance	3.20%	(167.00%)
Contingent purchase revaluation	0.00%	(1.00%)
Other	(0.30%)	(0.10%)
Total	18.90%	(141.80%)

Effective Income Tax Rate Reconciliation, Business Acquisition, Contingent Consideration, Percent

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Effective Income Tax Rate Reconciliation, Deferred Tax Adjustment, Percent

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Effective Income Tax Rate Reconciliation, Expired Tax Credit, 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 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 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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