Goodwill - (Details) - USD ($) $ in Thousands |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2016 |
Dec. 31, 2015 |
Dec. 31, 2014 |
|
| Goodwill [Roll Forward] | |||
| Beginning Balance | $ 361,680 | $ 421,019 | |
| Foreign currency translation adjustments | (1,078) | (59,339) | |
| Ending Balance | $ 360,602 | $ 361,680 | $ 421,019 |
| Maturity of corporate debt with similar credit risk | 20 years | ||
| US treasury bond maturity | 20 years | ||
| Discounted cash flow, discount rate | 8.67% | 9.41% | 9.89% |
| Institutional Products Group | |||
| Goodwill [Roll Forward] | |||
| Beginning Balance | $ 27,156 | $ 29,919 | |
| Foreign currency translation adjustments | 450 | (2,763) | |
| Ending Balance | $ 27,606 | 27,156 | $ 29,919 |
| Discounted cash flow sensitivity analysis discount rate rncrease | 1.00% | ||
| Europe | |||
| Goodwill [Roll Forward] | |||
| Beginning Balance | $ 334,524 | 391,100 | |
| Foreign currency translation adjustments | (1,528) | (56,576) | |
| Ending Balance | $ 332,996 | $ 334,524 | $ 391,100 |
| Discounted cash flow sensitivity analysis discount rate rncrease | 1.00% | ||