v3.19.3.a.u2

Redeemable Convertible Preferred Stock and Common Stock - Summary of Activity for Each Series of Outstanding Redeemable Convertible Preferred Stock (Details) - USD ($) $ in Thousands |  |  | 1 Months Ended | 12 Months Ended
--- | --- | --- | --- | ---
Dec. 11, 2018 | Aug. 10, 2016 | Sep. 30, 2018 | May 31, 2018 | Feb. 28, 2018 | Dec. 31, 2019 | Dec. 31, 2018
Increase (Decrease) in Temporary Equity [Roll Forward] |  |  |  |  |  |  |
Balance at beginning of period (in shares) |  |  |  |  |  | 0 | 448,686,791
Balance at beginning of period |  |  |  |  |  |  | $ 1,176,661
Conversion of redeemable convertible preferred stock into common stock |  |  |  |  |  |  | $ 1,833,561
Balance at end of period (in shares) | 508,539,515 |  |  |  |  | 0 | 0
Balance at end of period | $ 1,833,561 |  |  |  |  |  |
Issuance costs |  |  |  |  |  |  | $ 41,322
Series A Redeemable Convertible Preferred Stock |  |  |  |  |  |  |
Increase (Decrease) in Temporary Equity [Roll Forward] |  |  |  |  |  |  |
Balance at beginning of period (in shares) |  |  |  |  |  |  | 42,000,000
Balance at beginning of period |  |  |  |  |  |  | $ 182
Balance at end of period (in shares) | 42,000,000 |  |  |  |  |  |
Balance at end of period | $ 182 |  |  |  |  |  |
Series B Redeemable Convertible Preferred Stock |  |  |  |  |  |  |
Increase (Decrease) in Temporary Equity [Roll Forward] |  |  |  |  |  |  |
Balance at beginning of period (in shares) |  |  |  |  |  |  | 122,296,280
Balance at beginning of period |  |  |  |  |  |  | $ 770
Balance at end of period (in shares) | 122,296,280 |  |  |  |  |  |
Balance at end of period | $ 770 |  |  |  |  |  |
Series C Redeemable Convertible Preferred Stock |  |  |  |  |  |  |
Increase (Decrease) in Temporary Equity [Roll Forward] |  |  |  |  |  |  |
Balance at beginning of period (in shares) |  |  |  |  |  |  | 85,669,774
Balance at beginning of period |  |  |  |  |  |  | $ 36,238
Balance at end of period (in shares) | 85,669,774 |  |  |  |  |  |
Balance at end of period | $ 36,238 |  |  |  |  |  |
Series D Redeemable Convertible Preferred Stock |  |  |  |  |  |  |
Increase (Decrease) in Temporary Equity [Roll Forward] |  |  |  |  |  |  |
Balance at beginning of period (in shares) |  |  |  |  |  |  | 63,291,156
Balance at beginning of period |  |  |  |  |  |  | $ 164,059
Repurchase of redeemable convertible preferred stock (in shares) |  |  | (269,180) |  |  |  |
Repurchase of redeemable convertible preferred stock |  |  |  |  |  |  | $ (2,009)
Balance at end of period (in shares) | 63,021,976 |  |  |  |  |  |
Balance at end of period | $ 163,355 |  |  |  |  |  |
Series E Redeemable Convertible Preferred Stock |  |  |  |  |  |  |
Increase (Decrease) in Temporary Equity [Roll Forward] |  |  |  |  |  |  |
Balance at beginning of period (in shares) |  |  |  |  |  |  | 81,428,340
Balance at beginning of period |  |  |  |  |  |  | $ 501,880
Repurchase of redeemable convertible preferred stock (in shares) |  |  | (544,100) |  |  |  |
Repurchase of redeemable convertible preferred stock |  |  | $ (8,200) |  |  |  | $ (2,118)
Balance at end of period (in shares) | 80,884,240 |  |  |  |  |  |
Balance at end of period | $ 498,525 |  |  |  |  |  |
Series F Redeemable Convertible Preferred Stock |  |  |  |  |  |  |
Increase (Decrease) in Temporary Equity [Roll Forward] |  |  |  |  |  |  |
Balance at beginning of period (in shares) |  |  |  |  |  |  | 54,001,241
Balance at beginning of period |  |  |  |  |  |  | $ 473,532
Balance at end of period (in shares) | 54,001,241 |  |  |  |  |  |
Balance at end of period | $ 473,532 |  |  |  |  |  |
Issuance costs |  | $ 600 |  |  |  |  |
Series G Redeemable Convertible Preferred Stock |  |  |  |  |  |  |
Increase (Decrease) in Temporary Equity [Roll Forward] |  |  |  |  |  |  |
Issuance of redeemable convertible preferred stock, net of issuance costs |  |  |  |  |  |  | 51
Balance at end of period (in shares) | 55,666,004 |  |  |  |  |  |
Balance at end of period | $ 549,413 |  |  |  |  |  |
Issuance costs |  |  |  |  | $ 10,500 | $ 10,517 | 10,517
Series H Redeemable Convertible Preferred Stock |  |  |  |  |  |  |
Increase (Decrease) in Temporary Equity [Roll Forward] |  |  |  |  |  |  |
Balance at end of period (in shares) | 5,000,000 |  |  |  |  |  |
Balance at end of period | $ 111,546 |  |  |  |  |  |
Issuance costs |  |  |  | $ 400 |  | $ 474 | $ 474
Redeemable Convertible Preferred Stock |  |  |  |  |  |  |
Increase (Decrease) in Temporary Equity [Roll Forward] |  |  |  |  |  |  |
Balance at beginning of period (in shares) |  |  |  |  |  | 0 | 448,686,791
Balance at beginning of period |  |  |  |  |  | $ 0 | $ 1,176,661
Conversion of redeemable convertible preferred stock into common stock (in shares) |  |  |  |  |  |  | (508,539,515)
Conversion of redeemable convertible preferred stock into common stock |  |  |  |  |  |  | $ (1,833,561)
Balance at end of period (in shares) |  |  |  |  |  | 0 | 0
Balance at end of period |  |  |  |  |  | $ 0 | $ 0
Redeemable Convertible Preferred Stock | Series A Redeemable Convertible Preferred Stock |  |  |  |  |  |  |
Increase (Decrease) in Temporary Equity [Roll Forward] |  |  |  |  |  |  |
Balance at beginning of period (in shares) |  |  |  |  |  | 0 | 42,000,000
Balance at beginning of period |  |  |  |  |  | $ 0 | $ 182
Conversion of redeemable convertible preferred stock into common stock (in shares) |  |  |  |  |  |  | (42,000,000)
Conversion of redeemable convertible preferred stock into common stock |  |  |  |  |  |  | $ (182)
Balance at end of period (in shares) |  |  |  |  |  |  | 0
Balance at end of period |  |  |  |  |  |  | $ 0
Redeemable Convertible Preferred Stock | Series B Redeemable Convertible Preferred Stock |  |  |  |  |  |  |
Increase (Decrease) in Temporary Equity [Roll Forward] |  |  |  |  |  |  |
Balance at beginning of period (in shares) |  |  |  |  |  | 0 | 122,296,280
Balance at beginning of period |  |  |  |  |  | $ 0 | $ 770
Conversion of redeemable convertible preferred stock into common stock (in shares) |  |  |  |  |  |  | (122,296,280)
Conversion of redeemable convertible preferred stock into common stock |  |  |  |  |  |  | $ (770)
Balance at end of period (in shares) |  |  |  |  |  |  | 0
Balance at end of period |  |  |  |  |  |  | $ 0
Redeemable Convertible Preferred Stock | Series C Redeemable Convertible Preferred Stock |  |  |  |  |  |  |
Increase (Decrease) in Temporary Equity [Roll Forward] |  |  |  |  |  |  |
Balance at beginning of period (in shares) |  |  |  |  |  | 0 | 85,669,774
Balance at beginning of period |  |  |  |  |  | $ 0 | $ 36,238
Conversion of redeemable convertible preferred stock into common stock (in shares) |  |  |  |  |  |  | (85,669,774)
Conversion of redeemable convertible preferred stock into common stock |  |  |  |  |  |  | $ (36,238)
Balance at end of period (in shares) |  |  |  |  |  |  | 0
Balance at end of period |  |  |  |  |  |  | $ 0
Redeemable Convertible Preferred Stock | Series D Redeemable Convertible Preferred Stock |  |  |  |  |  |  |
Increase (Decrease) in Temporary Equity [Roll Forward] |  |  |  |  |  |  |
Balance at beginning of period (in shares) |  |  |  |  |  | 0 | 63,291,156
Balance at beginning of period |  |  |  |  |  | $ 0 | $ 164,059
Repurchase of redeemable convertible preferred stock (in shares) |  |  |  |  |  |  | (269,180)
Repurchase of redeemable convertible preferred stock |  |  |  |  |  |  | $ (704)
Conversion of redeemable convertible preferred stock into common stock (in shares) |  |  |  |  |  |  | (63,021,976)
Conversion of redeemable convertible preferred stock into common stock |  |  |  |  |  |  | $ (163,355)
Balance at end of period (in shares) |  |  |  |  |  |  | 0
Balance at end of period |  |  |  |  |  |  | $ 0
Redeemable Convertible Preferred Stock | Series E Redeemable Convertible Preferred Stock |  |  |  |  |  |  |
Increase (Decrease) in Temporary Equity [Roll Forward] |  |  |  |  |  |  |
Balance at beginning of period (in shares) |  |  |  |  |  | 0 | 81,428,340
Balance at beginning of period |  |  |  |  |  | $ 0 | $ 501,880
Repurchase of redeemable convertible preferred stock (in shares) |  |  |  |  |  |  | (544,100)
Repurchase of redeemable convertible preferred stock |  |  |  |  |  |  | $ (3,355)
Conversion of redeemable convertible preferred stock into common stock (in shares) |  |  |  |  |  |  | (80,884,240)
Conversion of redeemable convertible preferred stock into common stock |  |  |  |  |  |  | $ (498,525)
Balance at end of period (in shares) |  |  |  |  |  |  | 0
Balance at end of period |  |  |  |  |  |  | $ 0
Redeemable Convertible Preferred Stock | Series F Redeemable Convertible Preferred Stock |  |  |  |  |  |  |
Increase (Decrease) in Temporary Equity [Roll Forward] |  |  |  |  |  |  |
Balance at beginning of period (in shares) |  |  |  |  |  | 0 | 54,001,241
Balance at beginning of period |  |  |  |  |  | $ 0 | $ 473,532
Conversion of redeemable convertible preferred stock into common stock (in shares) |  |  |  |  |  |  | (54,001,241)
Conversion of redeemable convertible preferred stock into common stock |  |  |  |  |  |  | $ (473,532)
Balance at end of period (in shares) |  |  |  |  |  |  | 0
Balance at end of period |  |  |  |  |  |  | $ 0
Redeemable Convertible Preferred Stock | Series G Redeemable Convertible Preferred Stock |  |  |  |  |  |  |
Increase (Decrease) in Temporary Equity [Roll Forward] |  |  |  |  |  |  |
Balance at beginning of period (in shares) |  |  |  |  |  | 0 | 0
Balance at beginning of period |  |  |  |  |  | $ 0 | $ 0
Issuance of redeemable convertible preferred stock, net of issuance costs (in shares) |  |  |  |  |  |  | 55,666,004
Issuance of redeemable convertible preferred stock, net of issuance costs |  |  |  |  |  |  | $ 549,413
Conversion of redeemable convertible preferred stock into common stock (in shares) |  |  |  |  |  |  | (55,666,004)
Conversion of redeemable convertible preferred stock into common stock |  |  |  |  |  |  | $ (549,413)
Balance at end of period (in shares) |  |  |  |  |  |  | 0
Balance at end of period |  |  |  |  |  |  | $ 0
Redeemable Convertible Preferred Stock | Series H Redeemable Convertible Preferred Stock |  |  |  |  |  |  |
Increase (Decrease) in Temporary Equity [Roll Forward] |  |  |  |  |  |  |
Balance at beginning of period (in shares) |  |  |  |  |  | 0 | 0
Balance at beginning of period |  |  |  |  |  | $ 0 | $ 0
Issuance of redeemable convertible preferred stock, net of issuance costs (in shares) |  |  |  |  |  |  | 5,000,000
Issuance of redeemable convertible preferred stock, net of issuance costs |  |  |  |  |  |  | $ 111,546
Conversion of redeemable convertible preferred stock into common stock (in shares) |  |  |  |  |  |  | (5,000,000)
Conversion of redeemable convertible preferred stock into common stock |  |  |  |  |  |  | $ (111,546)
Balance at end of period (in shares) |  |  |  |  |  |  | 0
Balance at end of period |  |  |  |  |  |  | $ 0

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