Income taxes - Schedule of Reasons for the Difference Between Effective Tax Rates and U.S. Statutory Rate (Details) - USD ($) $ in Thousands |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2016 |
Dec. 31, 2015 |
Dec. 31, 2014 |
|
| Income Tax Disclosure [Abstract] | |||
| U.S. federal statutory rate (as a percent) | 35.00% | 35.00% | 35.00% |
| Income taxes at U.S. federal statutory rate of 35% | $ (24,362) | $ 3,998 | $ 44,503 |
| Net state income taxes | (1,841) | 466 | 976 |
| Foreign taxes | 38,211 | 38,052 | 32,991 |
| Foreign tax credits | (9,492) | (17,398) | (10,942) |
| Research and development credits | (1,024) | (24,938) | 0 |
| Unrecognized tax benefits | 4,051 | 6,187 | 403 |
| Valuation allowances | 123,892 | 38,284 | 17,846 |
| Proceeds from sale of joint venture assets | (3,641) | (5,315) | (5,162) |
| Capital contributions or distributions related to Spin-off | (2,887) | (77) | 0 |
| Other | 1,853 | 287 | (1,573) |
| Provision for income taxes | $ 124,760 | $ 39,546 | $ 79,042 |