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Marketable Debt and Equity Securities - Equity Securities Transactions (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021
Equity Securities
(Loss) gain on equity securities, net	$ (6,545)	$ 43,020	$ (9,974)	$ 56,002
Impairment	100	$ 0	100	$ 0
Preferred Stock
Equity Securities
Equity Securities without Readily Determinable Fair Value	31,124		31,124		$ 31,262
Astria/Catabasis \| Preferred Stock
Equity Securities
Equity Securities without Readily Determinable Fair Value	174		174		$ 312
Impairment	$ 100		$ 100
Technology License Agreement \| Viridian \| Common Stock
Equity Securities
Owned investment	717,144		717,144
License Agreement \| INmune \| Common Stock
Equity Securities
Owned investment	1,885,533		1,885,533