Summary of Significant Accounting Policies - Property, Plant and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Property, Plant and Equipment
Property, Plant and Equipment, gross	$ 4,637	$ 4,423
Less accumulated depreciation and amortization	(1,442)	(752)
Property, Plant and Equipment, net	3,195	3,671
Depreciation and amortization	690	834	$ 442
Leasehold improvements
Property, Plant and Equipment
Property, Plant and Equipment, gross	$ 2,705	2,705
Office equipment
Property, Plant and Equipment
Useful Life	5 years
Property, Plant and Equipment, gross	$ 70	70
Computers and software
Property, Plant and Equipment
Useful Life	3 years
Property, Plant and Equipment, gross	$ 625	411
Furniture, fixtures and equipment
Property, Plant and Equipment
Useful Life	5 years
Property, Plant and Equipment, gross	$ 1,237	$ 1,237

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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- Definition

The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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- Definition

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

No definition available.

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