Income Taxes - Schedule of effective income tax rate reconciliation (Details)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Income tax expense at statutory rate	21.00%	21.00%
Permanent items	(0.80%)	0.50%
Foreign rate differential	0.00%	(0.80%)
Impact of foreign operations	0.00%	(7.20%)
State taxes, net of federal benefit	3.00%	3.90%
Tax rate changes	0.00%	(0.60%)
Foreign exchange and other	0.70%	(0.60%)
Change in valuation allowance	(23.90%)	(16.20%)
Effective income tax rate	0.00%	0.00%

Effective Income Tax Rate Reconciliation, Foreign Exchange Other, 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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