Term Loan	6 Months Ended
Jun. 30, 2021
Term Loan [Abstract]
Term Loan	9. Term Loan The Company has a Loan and Security Agreement with Pacific Western Bank for a term loan not exceeding $12.0 million (the Loan Agreement) to finance leasehold improvements for the facilities in Redwood City, CA and other purposes permitted under the Loan Agreement, with an interest rate equal to the greater of 0.25% above the Prime Rate (as defined in the Loan Agreement) or 5.00%. As of June 30, 2021, no amounts had been drown under the Loan Agreement and the deferred debt issuance costs were $0.1 million and are included in other noncurrent assets on the Company’s consolidated balance sheets. There has been no material changes in the Loan Agreement from those disclosed in Note 9 to consolidated financial statements included in the Company's Annual Report on Form 10-K for the year ended December 31, 2020.

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-URI http://asc.fasb.org/topic&trid=2208564

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