Stockholders' Equity - Schedule of Reserved Shares of Common Stock for Issuance (Details) shares in Thousands	Sep. 30, 2020 shares
Class Of Stock [Line Items]
Total reserved shares of common stock	40,755
Equity Incentive Plan
Class Of Stock [Line Items]
Common stock awards granted under equity incentive plans	14,229
2017 Employee Stock Purchase Plan
Class Of Stock [Line Items]
Common stock awards available for issuance	5,089	[1]
2017 Plan
Class Of Stock [Line Items]
Common stock awards available for issuance	21,437

[1] The Company has not issued any common stock pursuant to the 2017 Employee Stock Purchase Plan.