Segment Information - Consolidated Total Assets (Details) - USD ($) $ in Thousands |
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
Dec. 31, 2014 |
---|---|---|---|---|
Segment Reporting, Asset Reconciling Item [Line Items] | ||||
Assets | $ 3,376,293 | $ 2,717,752 | ||
Cash and cash equivalents | 104,522 | 185,488 | $ 161,020 | $ 56,772 |
Reportable Segment | ||||
Segment Reporting, Asset Reconciling Item [Line Items] | ||||
Assets | 3,271,771 | 2,532,264 | ||
Reportable Segment | Domestic | ||||
Segment Reporting, Asset Reconciling Item [Line Items] | ||||
Assets | 2,437,485 | 1,778,481 | ||
Reportable Segment | International | ||||
Segment Reporting, Asset Reconciling Item [Line Items] | ||||
Assets | 433,513 | 352,898 | ||
Reportable Segment | Proprietary Products | ||||
Segment Reporting, Asset Reconciling Item [Line Items] | ||||
Assets | 400,773 | 400,885 | ||
Segment Reconciling Items | ||||
Segment Reporting, Asset Reconciling Item [Line Items] | ||||
Cash and cash equivalents | $ 104,522 | $ 185,488 |