Convertible Senior Notes - Schedule of Note Hedges (Details) - USD ($) shares in Thousands, $ in Thousands |
1 Months Ended | 3 Months Ended | 12 Months Ended | ||
|---|---|---|---|---|---|
Nov. 30, 2013 |
Jun. 30, 2017 |
Dec. 31, 2019 |
Dec. 31, 2018 |
Dec. 31, 2017 |
|
| Debt Instrument [Line Items] | |||||
| Purchase | $ 0 | $ 0 | $ 128,017 | ||
| 2022 Note Hedge | |||||
| Debt Instrument [Line Items] | |||||
| Purchase | $ 128,017 | ||||
| Shares (in shares) | 5,807 | ||||
| Shares as of December 31, 2019 (in shares) | 5,807 | ||||
| 2018 Note Hedge | |||||
| Debt Instrument [Line Items] | |||||
| Purchase | $ 135,815 | ||||
| Shares (in shares) | 7,783 | ||||
| Shares as of December 31, 2019 (in shares) | 0 | ||||