Basis of Presentation (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Basis of Presentation
Cash, cash equivalents and marketable securities	$ 176,100
Net loss	(16,538)	$ (12,625)
Net cash used in operations	(18,084)	$ (12,110)
Indefinite-lived intangible assets	$ 30,700		$ 30,700

Amount of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit.

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Sum of investments and unrestricted cash as of the balance sheet date.

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Amount of cash inflow (outflow) from operating activities, including discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities.

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Amount, after deduction of tax, noncontrolling interests, dividends on preferred stock and participating securities; of income (loss) available to common shareholders.

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