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v3.19.3.a.u2

INVESTMENTS (Details) - USD ($) $ in Thousands | Dec. 31, 2019 | Dec. 31, 2018
--- | --- | ---
Available-for-sale |  |
Amortized Cost | $ 545,771 |
Gross Unrealized Holding Gains | 285 |
Gross Unrealized Holding Losses | 88 |
Fair Value | 545,968 |
Continuous Unrealized Loss Position less than 12 Months | 88 |
Short-term |  |
Available-for-sale |  |
Amortized Cost |  | $ 320,740
Gross Unrealized Holding Gains |  | 16
Gross Unrealized Holding Losses |  | 106
Fair Value |  | 320,650
Continuous Unrealized Loss Position less than 12 Months |  | 106
Short-term | Commercial paper |  |
Available-for-sale |  |
Amortized Cost | 83,478 | 52,838
Fair Value | 83,478 | 52,838
Short-term | Certificates of deposit |  |
Available-for-sale |  |
Amortized Cost | 28,049 | 14,075
Fair Value | 28,049 | 14,075
Short-term | Municipal securities |  |
Available-for-sale |  |
Amortized Cost | 147,983 | 151,690
Gross Unrealized Holding Gains | 145 | 16
Gross Unrealized Holding Losses | 20 | 62
Fair Value | 148,108 | 151,644
Continuous Unrealized Loss Position less than 12 Months | 20 | 62
Short-term | U.S. government agency securities |  |
Available-for-sale |  |
Amortized Cost | 40,620 | 19,943
Gross Unrealized Holding Gains | 5 |
Gross Unrealized Holding Losses | 35 | 12
Fair Value | 40,590 | 19,931
Continuous Unrealized Loss Position less than 12 Months | 35 | 12
Short-term | U.S. treasuries |  |
Available-for-sale |  |
Amortized Cost | 211,055 | 78,189
Gross Unrealized Holding Gains | 134 |
Gross Unrealized Holding Losses | 31 | 32
Fair Value | 211,158 | 78,157
Continuous Unrealized Loss Position less than 12 Months | 31 | 32
Short-term | Variable rate demand notes |  |
Available-for-sale |  |
Amortized Cost | 21,680 | 4,005
Fair Value | 21,680 | $ 4,005
Long-term | Municipal securities |  |
Available-for-sale |  |
Amortized Cost | 1,562 |
Gross Unrealized Holding Losses | 1 |
Fair Value | 1,561 |
Continuous Unrealized Loss Position less than 12 Months | 1 |
Long-term | U.S. government agency securities |  |
Available-for-sale |  |
Amortized Cost | 5,267 |
Gross Unrealized Holding Losses | 1 |
Fair Value | 5,266 |
Continuous Unrealized Loss Position less than 12 Months | 1 |
Long-term | U.S. treasuries |  |
Available-for-sale |  |
Amortized Cost | 6,077 |
Gross Unrealized Holding Gains | 1 |
Fair Value | $ 6,078 |

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