Balance Sheet Components (Available For Sale Investments) (Details) - Short-term Investments - USD ($) $ in Thousands |
Sep. 30, 2016 |
Dec. 31, 2015 |
|---|---|---|
| Schedule of Available-for-sale Securities [Line Items] | ||
| Amortized Cost | $ 3,250 | $ 7,420 |
| Unrealized Gains | 0 | 0 |
| Unrealized Losses | (1) | (5) |
| Estimated Fair Value | 3,249 | 7,415 |
| Commercial paper | ||
| Schedule of Available-for-sale Securities [Line Items] | ||
| Amortized Cost | 1,493 | |
| Unrealized Gains | 0 | |
| Unrealized Losses | 0 | |
| Estimated Fair Value | 1,493 | |
| Corporate debt securities | ||
| Schedule of Available-for-sale Securities [Line Items] | ||
| Amortized Cost | 1,757 | 7,420 |
| Unrealized Gains | 0 | 0 |
| Unrealized Losses | (1) | (5) |
| Estimated Fair Value | $ 1,756 | $ 7,415 |