Stockholders' Equity - Schedule of Common Stock Reserved for Future Issuance (Parenthetical) (Details) - shares	Jan. 01, 2020	Sep. 30, 2020	Dec. 31, 2019
Class Of Stock [Line Items]
Treasury stock, shares at cost		534,000	465,000
2016 Equity Incentive Plan
Class Of Stock [Line Items]
Number of authorized shares increased	387,000
2016 Employee Stock Purchase Plan
Class Of Stock [Line Items]
Number of authorized shares increased	97,000