Financial Instruments - Amortized Cost and Fair Value of Available-for-Sale Securities by Contractual Maturity (Detail) - USD ($) $ in Thousands |
Jun. 30, 2019 |
Dec. 31, 2018 |
|---|---|---|
| Amortized cost | ||
| Maturing within one year, Amortized cost | $ 178,095 | $ 287,755 |
| Maturing in one to five years, Amortized cost | 8,833 | 23,169 |
| Total available-for-sale securities, Amortized cost | 186,928 | 310,924 |
| Estimated Fair value | ||
| Maturing within one year, Estimated fair value | 178,197 | 287,469 |
| Maturing in one to five years, Estimated fair value | 8,904 | 23,115 |
| Total available-for-sale securities, Estimated fair value | $ 187,101 | $ 310,584 |
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- Definition Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in second through fifth 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), with single maturity date and allocated without single maturity date, maturing in second through fifth 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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- References No definition available.
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- Definition Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- References No definition available.
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- Definition Amortized cost of investment in debt security measured at fair value with change recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, 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), 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 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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