Unconsolidated Investments - Summarized Operating Results of Unconsolidated Investees (Detail) - USD ($) $ in Thousands |
3 Months Ended | |
|---|---|---|
Mar. 31, 2018 |
Mar. 31, 2017 |
|
| Equity Method Investments and Joint Ventures [Abstract] | ||
| Revenue | $ 109,533 | $ 100,359 |
| Cost of revenue | 30,337 | 29,589 |
| Operating expenses | 19,154 | 714 |
| Other expense | 20,851 | 22,841 |
| Net income (loss) | $ 39,191 | $ 47,215 |