Cash, Cash Equivalents and Short-Term Investments - Short-term Investments In Unrealized Loss Positions (Details) $ in Millions |
Dec. 31, 2018
USD ($)
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Fair value | |
Less than 12 months | $ 337.3 |
12 months or greater | 0.0 |
Total | 337.3 |
Unrealized losses | |
Less than 12 months | (0.6) |
12 months or greater | 0.0 |
Total | (0.6) |
Corporate notes and obligations | |
Fair value | |
Less than 12 months | 209.5 |
12 months or greater | 0.0 |
Total | 209.5 |
Unrealized losses | |
Less than 12 months | (0.5) |
12 months or greater | 0.0 |
Total | (0.5) |
U.S. Treasury securities | |
Fair value | |
Less than 12 months | 127.8 |
12 months or greater | 0.0 |
Total | 127.8 |
Unrealized losses | |
Less than 12 months | (0.1) |
12 months or greater | 0.0 |
Total | $ (0.1) |
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- References No definition available.
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- References No definition available.
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- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for less than 12 months. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for less than 12 months. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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