Investments - Schedule of Fair Values of Available For Sale Debt Investments by Contractual Maturity (Detail) - USD ($) $ in Thousands |
Dec. 31, 2019 |
Dec. 31, 2018 |
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| Investments, Debt and Equity Securities [Abstract] | ||
| Due in 1 year or less | $ 355,407 | $ 375,625 |
| Due in 1 - 2 years | 58,322 | 240,614 |
| Due in 3 years | 0 | 36,870 |
| Instruments not due at a single maturity date | 122,900 | 61,023 |
| Total cash equivalents and investments | $ 536,629 | $ 714,132 |
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- Definition Available for sale securities debt maturities after one through two years fair value. No definition available.
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- Definition Available for sale securities debt maturities within three year fair value. No definition available.
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- Definition Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), maturing in next fiscal year following latest fiscal year. Excludes interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), without single maturity date and not allocated over maturity grouping. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References No definition available.
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