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v3.20.2

Fair Value Measurements and Available for Sale Investments - Available-for-sale Investments (Details) - USD ($) $ in Thousands | 9 Months Ended |
--- | --- | ---
Sep. 30, 2020 | Dec. 31, 2019
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | $ 164,902 |
Gross Unrealized Gains | 481 |
Gross Unrealized Losses | (14) |
Total Fair Value | 165,369 |
Short-term investments | 129,192 | $ 203,210
Long-term investments | 36,177 | $ 54,305
Agency securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 15,790 |
Gross Unrealized Gains | 16 |
Gross Unrealized Losses | (1) |
Total Fair Value | 15,805 |
Short-term investments | $ 800 |
Investments outstanding, maturity date range (in years) | 1 year |
Long-term investments | $ 15,000 |
Agency securities | Minimum |  |
Debt Securities, Available-for-sale [Line Items] |  |
Investments outstanding, maturity date range (in years) | 1 year |
Agency securities | Maximum |  |
Debt Securities, Available-for-sale [Line Items] |  |
Investments outstanding, maturity date range (in years) | 2 years |
Certificates of deposit |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | $ 3,696 |
Gross Unrealized Gains | 17 |
Gross Unrealized Losses | 0 |
Total Fair Value | 3,713 |
Short-term investments | $ 3,000 |
Investments outstanding, maturity date range (in years) | 1 year |
Long-term investments | $ 700 |
Certificates of deposit | Minimum |  |
Debt Securities, Available-for-sale [Line Items] |  |
Investments outstanding, maturity date range (in years) | 1 year |
Certificates of deposit | Maximum |  |
Debt Securities, Available-for-sale [Line Items] |  |
Investments outstanding, maturity date range (in years) | 2 years |
Commercial and corporate obligations |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | $ 38,590 |
Gross Unrealized Gains | 105 |
Gross Unrealized Losses | (3) |
Total Fair Value | $ 38,692 |
Commercial and corporate obligations | Maximum |  |
Debt Securities, Available-for-sale [Line Items] |  |
Investments outstanding, maturity date range (in years) | 1 year |
U.S. Treasury securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | $ 106,826 |
Gross Unrealized Gains | 343 |
Gross Unrealized Losses | (10) |
Total Fair Value | 107,159 |
Short-term investments | 86,700 |
Long-term investments | $ 20,400 |
U.S. Treasury securities | Minimum |  |
Debt Securities, Available-for-sale [Line Items] |  |
Investments outstanding, maturity date range (in years) | 1 year |
U.S. Treasury securities | Maximum |  |
Debt Securities, Available-for-sale [Line Items] |  |
Investments outstanding, maturity date range (in years) | 2 years |

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