Derivatives Fair Value of Convertible Debt Hedges (Details) - USD ($) |
12 Months Ended | |
|---|---|---|
Dec. 31, 2016 |
Dec. 31, 2015 |
|
| Derivative Instruments and Hedging Activities Disclosures [Line Items] | ||
| Convertible Debt Conversion Feature, Fair Value | $ (30,708,000) | $ 0 |
| Convertible note hedge asset | 25,471,000 | $ 0 |
| Convertible Debt Conversion Feature Gain (Loss) | 3,772,000 | |
| Fair Values Convertible Debt Hedges, Net | (5,237,000) | |
| Convertible Debt Note Hedge Gain (Loss) | (2,504,000) | |
| Fair Values Convertible Debt Hedges, Gain (Loss) | $ 1,268,000 |