Fair Value Measurements (Fair Value Liabilities Measured on Recurring Basis Unobservable Inputs Reconciliation) (Details) - USD ($) $ in Thousands |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2017 |
Sep. 30, 2016 |
Sep. 30, 2017 |
Sep. 30, 2016 |
|
| Fair Value Measurements [Abstract] | ||||
| Beginning Balance | $ 142 | $ 383 | $ 195 | $ 455 |
| Change in Fair Value | 0 | 0 | (53) | (72) |
| Ending Balance | $ 142 | $ 383 | $ 142 | $ 383 |