(Notes)	6 Months Ended
Jun. 30, 2019
Subsequent Events [Abstract]
Subsequent Event	Subsequent EventOn July 9, 2019, the Company entered into a collaboration and license agreement with I-Mab Biopharma (I-Mab), a China and U.S.-based clinical-stage biopharmaceutical company, to develop and commercialize enoblituzumab. The Company will receive an upfront payment of $15.0 million in connection with the collaboration. Assuming successful development and commercialization, the Company will also be eligible to receive additional development and regulatory milestone payments of up to $135.0 million. In addition, I-Mab will pay tiered double-digit royalties (ranging from mid-teens to twenty percent) based on annual net sales in its territories.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-URI http://asc.fasb.org/topic&trid=2122774

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