Net (Loss) Income per Share Attributable to Common Stockholders - Antidilutive Securities (Details) - shares shares in Thousands |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 29, 2019 |
Jun. 30, 2018 |
Jun. 29, 2019 |
Jun. 30, 2018 |
|
| Stock options | ||||
| Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] | ||||
| Antidilutive securities (shares) | 3,189 | 4,002 | 3,189 | 846 |
| Restricted stock units | ||||
| Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] | ||||
| Antidilutive securities (shares) | 2,412 | 2,514 | 2,412 | 684 |
| Series A Redeemable Convertible Preferred Stock (as converted to common stock) | ||||
| Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] | ||||
| Antidilutive securities (shares) | 5,183 | 4,915 | 5,183 | 4,915 |