0000001 - Document - Cover link:presentationLink link:calculationLink link:definitionLink 9952151 - Statement - Condensed Balance Sheets (Unaudited) link:presentationLink link:calculationLink link:definitionLink 9952152 - Statement - Condensed Balance Sheets (Unaudited) (Parenthetical) link:presentationLink link:calculationLink link:definitionLink 9952153 - Statement - Condensed Statements of Operations and Comprehensive Loss (Unaudited) link:presentationLink link:calculationLink link:definitionLink 9952154 - Statement - Condensed Statements of Stockholders’ Equity (Unaudited) link:presentationLink link:calculationLink link:definitionLink 9952155 - Statement - Condensed Statements of Cash Flows (Unaudited) link:presentationLink link:calculationLink link:definitionLink 9952156 - Disclosure - Organization and Description of Business link:presentationLink link:calculationLink link:definitionLink 9952157 - Disclosure - Summary of Significant Accounting Policies link:presentationLink link:calculationLink link:definitionLink 9952158 - Disclosure - Financial Instruments link:presentationLink link:calculationLink link:definitionLink 9952159 - Disclosure - Property and Equipment, net link:presentationLink link:calculationLink link:definitionLink 9952160 - Disclosure - Prepaid Expenses and Other Current Assets link:presentationLink link:calculationLink link:definitionLink 9952161 - Disclosure - Accrued Liabilities link:presentationLink link:calculationLink link:definitionLink 9952162 - Disclosure - Long-term Debt link:presentationLink link:calculationLink link:definitionLink 9952163 - Disclosure - Novartis Collaboration and License Agreement ("the Novartis Agreement") link:presentationLink link:calculationLink link:definitionLink 9952164 - Disclosure - Preferred Stock link:presentationLink link:calculationLink link:definitionLink 9952165 - Disclosure - Common Stock link:presentationLink link:calculationLink link:definitionLink 9952166 - Disclosure - Equity Incentive Plans and Stock-Based Compensation link:presentationLink link:calculationLink link:definitionLink 9952167 - Disclosure - Income Taxes link:presentationLink link:calculationLink link:definitionLink 9952168 - Disclosure - Commitments and Contingencies link:presentationLink link:calculationLink link:definitionLink 9952169 - Disclosure - Leases link:presentationLink link:calculationLink link:definitionLink 9952170 - Disclosure - Defined Contribution Plan link:presentationLink link:calculationLink link:definitionLink 9952171 - Disclosure - Net Loss Per Share Attributable to Common Stockholders link:presentationLink link:calculationLink link:definitionLink 9954471 - Disclosure - Summary of Significant Accounting Policies (Policies) link:presentationLink link:calculationLink link:definitionLink 9954472 - Disclosure - Financial Instruments (Tables) link:presentationLink link:calculationLink link:definitionLink 9954473 - Disclosure - Property and Equipment, net (Tables) link:presentationLink link:calculationLink link:definitionLink 9954474 - Disclosure - Prepaid Expenses and Other Current Assets (Tables) link:presentationLink link:calculationLink link:definitionLink 9954475 - Disclosure - Accrued Liabilities (Tables) link:presentationLink link:calculationLink link:definitionLink 9954476 - Disclosure - Long-term Debt (Tables) link:presentationLink link:calculationLink link:definitionLink 9954477 - Disclosure - Common Stock (Tables) link:presentationLink link:calculationLink link:definitionLink 9954478 - Disclosure - Equity Incentive Plans and Stock-Based Compensation (Tables) link:presentationLink link:calculationLink link:definitionLink 9954479 - Disclosure - Leases (Tables) link:presentationLink link:calculationLink link:definitionLink 9954480 - Disclosure - Net Loss Per Share Attributable to Common Stockholders (Tables) link:presentationLink link:calculationLink link:definitionLink 9954481 - Disclosure - Organization and Description of Business (Details) link:presentationLink link:calculationLink link:definitionLink 9954482 - Disclosure - Financial Instruments - Narrative (Details) link:presentationLink link:calculationLink link:definitionLink 9954483 - Disclosure - Financial Instruments - Schedule of Cash and Cash Equivalents, Money Market Funds and Short-term Investments by Significant Investment Category (Details) link:presentationLink link:calculationLink link:definitionLink 9954484 - Disclosure - Property and Equipment, net - Schedule of Property and Equipment (Details) link:presentationLink link:calculationLink link:definitionLink 9954485 - Disclosure - Property and Equipment, net - Narrative (Details) link:presentationLink link:calculationLink link:definitionLink 9954486 - Disclosure - Prepaid Expenses and Other Current Assets (Details) link:presentationLink link:calculationLink link:definitionLink 9954487 - Disclosure - Accrued Liabilities (Details) link:presentationLink link:calculationLink link:definitionLink 9954488 - Disclosure - Long-term Debt - Narrative (Details) link:presentationLink link:calculationLink link:definitionLink 9954489 - Disclosure - Long-term Debt - Schedule of Maturities of Long-Term Debt (Details) link:presentationLink link:calculationLink link:definitionLink 9954490 - 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Schedule of Black-Scholes Option Pricing Model to Estimate Stock-based Compensation Expense for Stock Option Awards (Details) link:presentationLink link:calculationLink link:definitionLink 9954497 - Disclosure - Equity Incentive Plans and Stock-Based Compensation - Schedule of Option Activity Under the 2015 Plan and 2020 Plan (Details) link:presentationLink link:calculationLink link:definitionLink 9954498 - Disclosure - Equity Incentive Plans and Stock-Based Compensation - Restricted Stock Units - Narrative (Details) link:presentationLink link:calculationLink link:definitionLink 9954499 - Disclosure - Equity Incentive Plans and Stock-Based Compensation - Schedule of Restricted Stock Activity (Details) link:presentationLink link:calculationLink link:definitionLink 9954500 - Disclosure - Equity Incentive Plans and Stock-Based Compensation - Performance-Based Restricted Stock Units - Narrative (Details) link:presentationLink link:calculationLink link:definitionLink 9954501 - Disclosure - Equity Incentive Plans and Stock-Based Compensation - Schedule of TSR PSU Valuation Assumptions (Details) link:presentationLink link:calculationLink link:definitionLink 9954502 - Disclosure - Equity Incentive Plans and Stock-Based Compensation - 2020 Employee Stock Purchase Plan - Narrative (Details) link:presentationLink link:calculationLink link:definitionLink 9954503 - Disclosure - Equity Incentive Plans and Stock-Based Compensation - 2020 Employee Stock Purchase Plan - Schedule of Black-Scholes Option Pricing Model to Estimate Stock-based Compensation Expense for 2020 Employee Stock Purchase Plan (Details) link:presentationLink link:calculationLink link:definitionLink 9954504 - Disclosure - Equity Incentive Plans and Stock-Based Compensation - Schedule of Stock-based Compensation Expense (Details) link:presentationLink link:calculationLink link:definitionLink 9954505 - Disclosure - Income Taxes (Details) link:presentationLink link:calculationLink link:definitionLink 9954506 - Disclosure - Commitments and Contingencies (Details) link:presentationLink link:calculationLink link:definitionLink 9954507 - Disclosure - Leases - Narrative (Details) link:presentationLink link:calculationLink link:definitionLink 9954508 - Disclosure - Leases - Schedule of Operating Lease Liability (Details) link:presentationLink link:calculationLink link:definitionLink 9954508 - Disclosure - Leases - Schedule of Operating Lease Liability (Details) link:presentationLink link:calculationLink link:definitionLink 9954509 - Disclosure - Leases - Schedule of Weighted-average Remaining Lease Terms and Discount Rates (Details) link:presentationLink link:calculationLink link:definitionLink 9954510 - Disclosure - Leases - Schedule of Operating and Variable Lease Cost (Details) link:presentationLink link:calculationLink link:definitionLink 9954511 - Disclosure - Defined Contribution Plan (Details) link:presentationLink link:calculationLink link:definitionLink 9954512 - Disclosure - Net Loss Per Share Attributable to Common Stockholders (Details) link:presentationLink link:calculationLink link:definitionLink