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The aggregate amount of recurring noncash expense charged against earnings in the period to allocate the cost of assets over their estimated remaining economic lives.

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For contingent consideration arrangements recognized in connection with a business combination, this element represents an estimate of the high-end of the potential range (undiscounted) of the consideration which may be paid.

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Amount of asset recognized arising from contingent consideration in a business combination.

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Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

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Amount of deferred policy acquisition cost capitalized on contract remaining in force.

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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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BeiGene Exclusive Option and License Agreement (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Jan. 03, 2020
BeiGene Exclusive Option and License Agreement
Up-front fee			$ 3,000
Contract acquisition costs	$ 270		270
Amortization expense	0	$ 34	0	$ 68
Exclusive Option and License Agreement
BeiGene Exclusive Option and License Agreement
Future option exercise and milestone payments, maximum					$ 132,000
License
BeiGene Exclusive Option and License Agreement
Revenue recognized	$ 0	$ 375	0	750
Royalty
BeiGene Exclusive Option and License Agreement
Revenue recognized			$ 0	$ 0
Exclusive Option and License Agreement
BeiGene Exclusive Option and License Agreement
Upfront cash payment					$ 3,000