Organization and Summary of Significant Accounting Policies Organization and Significant Accounting Policies - Segment Reporting and Geographic Information (Details) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
|
| Revenues from External Customers and Long-Lived Assets [Line Items] | |||
| Number of Reportable Segments | 1 | ||
| Revenue, Percentage | 100.00% | 100.00% | 100.00% |
| Total Revenue | $ 718.5 | $ 573.3 | $ 402.0 |
| International [Member] | |||
| Revenues from External Customers and Long-Lived Assets [Line Items] | |||
| Revenue, Percentage | 17.00% | 13.00% | 14.00% |
| Total Revenue | $ 122.3 | $ 75.8 | $ 54.6 |
| UNITED STATES | |||
| Revenues from External Customers and Long-Lived Assets [Line Items] | |||
| Revenue, Percentage | 83.00% | 87.00% | 86.00% |
| Total Revenue | $ 596.2 | $ 497.5 | $ 347.4 |