Goodwill and Intangible Assets - Summary of Identifiable Intangible Assets (Details) - USD ($) $ in Thousands |
Dec. 31, 2017 |
Dec. 31, 2016 |
|---|---|---|
| Finite-Lived Intangible Assets [Line Items] | ||
| Gross | $ 283,108 | $ 270,131 |
| Accumulated Amortization | (100,557) | (75,459) |
| Net | 182,551 | 194,672 |
| Acquired Internal Use Software | ||
| Finite-Lived Intangible Assets [Line Items] | ||
| Gross | 14,000 | 14,000 |
| Accumulated Amortization | (14,000) | (12,665) |
| Net | 0 | 1,335 |
| Technology | ||
| Finite-Lived Intangible Assets [Line Items] | ||
| Gross | 68,550 | 68,550 |
| Accumulated Amortization | (25,639) | (18,529) |
| Net | 42,911 | 50,021 |
| Merchant Relationships | ||
| Finite-Lived Intangible Assets [Line Items] | ||
| Gross | 181,000 | 181,000 |
| Accumulated Amortization | (56,018) | (40,934) |
| Net | 124,982 | 140,066 |
| Other Intangibles | ||
| Finite-Lived Intangible Assets [Line Items] | ||
| Gross | 19,558 | 6,581 |
| Accumulated Amortization | (4,900) | (3,331) |
| Net | $ 14,658 | $ 3,250 |