Income taxes - Schedule of Components of Income (Loss) Before Income Taxes (Details) - USD ($) $ in Thousands |
3 Months Ended | 12 Months Ended | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
Dec. 31, 2016 |
Sep. 30, 2016 |
Jun. 30, 2016 |
Mar. 31, 2016 |
Dec. 31, 2015 |
Sep. 30, 2015 |
Jun. 30, 2015 |
Mar. 31, 2015 |
Dec. 31, 2016 |
Dec. 31, 2015 |
Dec. 31, 2014 |
|
| Income Tax Disclosure [Abstract] | |||||||||||
| United States | $ (129,864) | $ (7,702) | $ 84,161 | ||||||||
| Foreign | 60,258 | 19,122 | 42,990 | ||||||||
| Income (loss) before income taxes | $ (26,642) | $ (32,312) | $ (106,582) | $ (28,830) | $ (22,443) | $ (9,598) | $ (14,630) | $ 18,545 | $ (69,606) | $ 11,420 | $ 127,151 |