Condensed Consolidated Statements of Change in Convertible Preferred Stock and Shareholders' Equity (Deficit) - USD ($) $ in Thousands | Total | Common Stock (Class A and B) | Additional Paid-in Capital | Accumulated Deficit | Accumulated Other Comprehensive Income |
Beginning balance, convertible preferred stock (in shares) at Jan. 31, 2018 | 67,619,377 | | | | |
Beginning balance, convertible preferred stock at Jan. 31, 2018 | $ 112,687 | | | | |
Increase (Decrease) in Temporary Equity [Roll Forward] | | | | | |
Conversion of convertible preferred stock to common stock in connection with initial public offering (in shares) | (67,619,377) | | | | |
Conversion of convertible preferred stock to common stock in connection with initial public offering | $ (112,687) | | | | |
Ending balance, convertible preferred stock (in shares) at Oct. 31, 2018 | 0 | | | | |
Ending balance, convertible preferred stock at Oct. 31, 2018 | $ 0 | | | | |
Beginning balance, common stock (in shares) at Jan. 31, 2018 | | 20,280,741 | | | |
Beginning balance at Jan. 31, 2018 | (80,741) | $ 0 | $ 25,892 | $ (106,633) | $ 0 |
Increase (Decrease) in Stockholders' Equity [Roll Forward] | | | | | |
Issuance of common stock under employee stock plans (in shares) | | 2,675,607 | | | |
Issuance of common stock under employee stock plans | 6,757 | | 6,757 | | |
Issuance of common stock upon net exercise of warrant (in shares) | | 134,603 | | | |
Issuance of common stock upon net exercise of warrant | 2,598 | | 2,598 | | |
Issuance of common stock in connection with initial public offering, net of underwriting discounts, commissions, and issuance costs (in shares) | | 11,745,088 | | | |
Issuance of common stock in connection with initial public offering, net of underwriting discounts, commissions, and issuance costs | 160,413 | | 160,413 | | |
Conversion of convertible preferred stock to common stock in connection with initial public offering (in shares) | | 68,479,732 | | | |
Conversion of convertible preferred stock to common stock in connection with initial public offering | 112,687 | | 112,687 | | |
Share-based compensation expense | 12,098 | | 12,098 | | |
Comprehensive loss | (42,198) | | | (42,198) | |
Ending balance, common stock (in shares) at Oct. 31, 2018 | | 103,315,771 | | | |
Ending balance at Oct. 31, 2018 | $ 171,614 | $ 0 | 320,445 | (148,831) | 0 |
Beginning balance, convertible preferred stock (in shares) at Jul. 31, 2018 | 0 | | | | |
Beginning balance, convertible preferred stock at Jul. 31, 2018 | $ 0 | | | | |
Ending balance, convertible preferred stock (in shares) at Oct. 31, 2018 | 0 | | | | |
Ending balance, convertible preferred stock at Oct. 31, 2018 | $ 0 | | | | |
Beginning balance, common stock (in shares) at Jul. 31, 2018 | | 102,652,995 | | | |
Beginning balance at Jul. 31, 2018 | 176,427 | $ 0 | 309,691 | (133,264) | 0 |
Increase (Decrease) in Stockholders' Equity [Roll Forward] | | | | | |
Issuance of common stock under employee stock plans (in shares) | | 662,776 | | | |
Issuance of common stock under employee stock plans | 4,596 | | 4,596 | | |
Share-based compensation expense | 6,158 | | 6,158 | | |
Comprehensive loss | (15,567) | | | (15,567) | |
Ending balance, common stock (in shares) at Oct. 31, 2018 | | 103,315,771 | | | |
Ending balance at Oct. 31, 2018 | $ 171,614 | $ 0 | 320,445 | (148,831) | 0 |
Beginning balance, convertible preferred stock (in shares) at Jan. 31, 2019 | 0 | | | | |
Beginning balance, convertible preferred stock at Jan. 31, 2019 | $ 0 | | | | |
Ending balance, convertible preferred stock (in shares) at Oct. 31, 2019 | 0 | | | | |
Ending balance, convertible preferred stock at Oct. 31, 2019 | $ 0 | | | | |
Beginning balance, common stock (in shares) at Jan. 31, 2019 | | 104,971,443 | | | |
Beginning balance at Jan. 31, 2019 | 166,992 | $ 0 | 327,510 | (160,518) | 0 |
Increase (Decrease) in Stockholders' Equity [Roll Forward] | | | | | |
Issuance of common stock under employee stock plans (in shares) | | 3,374,026 | | | |
Issuance of common stock under employee stock plans | 22,431 | | 22,431 | | |
Issuance of common stock in connection with initial public offering, net of underwriting discounts, commissions, and issuance costs (in shares) | | 9,025,000 | | | |
Issuance of common stock in connection with initial public offering, net of underwriting discounts, commissions, and issuance costs | 378,982 | | 378,982 | | |
Share-based compensation expense | 26,411 | | 26,411 | | |
Comprehensive loss | (67,779) | | | (67,779) | |
Ending balance, common stock (in shares) at Oct. 31, 2019 | | 117,370,469 | | | |
Ending balance at Oct. 31, 2019 | $ 527,037 | $ 0 | 755,334 | (228,297) | 0 |
Beginning balance, convertible preferred stock (in shares) at Jul. 31, 2019 | 0 | | | | |
Beginning balance, convertible preferred stock at Jul. 31, 2019 | $ 0 | | | | |
Ending balance, convertible preferred stock (in shares) at Oct. 31, 2019 | 0 | | | | |
Ending balance, convertible preferred stock at Oct. 31, 2019 | $ 0 | | | | |
Beginning balance, common stock (in shares) at Jul. 31, 2019 | | 116,347,632 | | | |
Beginning balance at Jul. 31, 2019 | 536,941 | $ 0 | 736,383 | (199,442) | 0 |
Increase (Decrease) in Stockholders' Equity [Roll Forward] | | | | | |
Issuance of common stock under employee stock plans (in shares) | | 1,022,837 | | | |
Issuance of common stock under employee stock plans | 8,329 | | 8,329 | | |
Issuance of common stock in connection with initial public offering, net of underwriting discounts, commissions, and issuance costs | 12 | | 12 | | |
Share-based compensation expense | 10,610 | | 10,610 | | |
Comprehensive loss | (28,855) | | | (28,855) | |
Ending balance, common stock (in shares) at Oct. 31, 2019 | | 117,370,469 | | | |
Ending balance at Oct. 31, 2019 | $ 527,037 | $ 0 | $ 755,334 | $ (228,297) | $ 0 |