Balance Sheet Details - Short-term Marketable Securities (Details) - USD ($) $ in Millions |
Mar. 31, 2020 |
Dec. 31, 2019 |
---|---|---|
Debt securities, available for sale: | ||
Amortized Cost | $ 923.2 | $ 1,086.7 |
Gross Unrealized Gains | 3.6 | 0.5 |
Gross Unrealized Losses | (0.9) | (0.1) |
Estimated Market Value | 925.9 | 1,087.1 |
U.S. government agencies | ||
Debt securities, available for sale: | ||
Amortized Cost | 620.4 | 675.6 |
Gross Unrealized Gains | 3.5 | 0.4 |
Gross Unrealized Losses | 0.0 | 0.0 |
Estimated Market Value | 623.9 | 676.0 |
Commercial paper | ||
Debt securities, available for sale: | ||
Amortized Cost | 189.1 | 248.1 |
Gross Unrealized Gains | 0.1 | 0.1 |
Gross Unrealized Losses | (0.1) | 0.0 |
Estimated Market Value | 189.1 | 248.2 |
Corporate debt | ||
Debt securities, available for sale: | ||
Amortized Cost | 113.7 | 163.0 |
Gross Unrealized Gains | 0.0 | 0.0 |
Gross Unrealized Losses | (0.8) | (0.1) |
Estimated Market Value | $ 112.9 | $ 162.9 |