Quarterly Financial Data (unaudited) - Summary of Unaudited Quarterly Financial Information (Details) - USD ($) $ / shares in Units, $ in Thousands |
3 Months Ended | 12 Months Ended | |||||||||
---|---|---|---|---|---|---|---|---|---|---|---|
Dec. 31, 2017 |
Sep. 30, 2017 |
Jun. 30, 2017 |
Mar. 31, 2017 |
Dec. 31, 2016 |
Sep. 30, 2016 |
Jun. 30, 2016 |
Mar. 31, 2016 |
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
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Selected Quarterly Financial Information [Abstract] | |||||||||||
Revenue | $ 2,414 | $ 198 | $ 5 | $ 111 | $ 17 | $ 476 | $ 133 | ||||
Operating expenses | 99,248 | 83,911 | $ 78,441 | $ 69,954 | 70,554 | 65,894 | 58,070 | $ 53,622 | 331,554 | 248,140 | $ 147,738 |
Net loss | $ (81,731) | $ (79,227) | $ (72,891) | $ (68,290) | $ (71,287) | $ (64,907) | $ (56,923) | $ (52,757) | $ (302,139) | $ (245,874) | $ (145,618) |
Net loss per share, basic and diluted | $ (1.89) | $ (1.87) | $ (1.72) | $ (1.63) | $ (1.75) | $ (1.64) | $ (1.46) | $ (1.35) | $ (7.12) | $ (6.21) | $ (3.96) |