Composition of Certain Financial Statement Captions - Schedule of available-for-sale investments by contractual maturity date (Details) - USD ($) $ in Thousands |
Dec. 31, 2017 |
Dec. 31, 2016 |
|---|---|---|
| Adjusted Cost | ||
| Due in one year or less | $ 354,553 | $ 92,914 |
| Due after one year through three years | 6,251 | |
| Total | 354,553 | 99,165 |
| Fair Value | ||
| Due in one year or less | 354,553 | 92,861 |
| Due after one year through three years | 6,252 | |
| Total | $ 354,553 | $ 99,113 |
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- Definition Represents the amount of available-for-sale debt securities at cost, net of adjustments, maturing in the second fiscal year through the three fiscal years following the latest fiscal year. No definition available.
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- Definition Represents the amount of available-for-sale debt securities at fair value maturing in the second fiscal year through the three fiscal years following the latest fiscal year. No definition available.
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- Definition This item represents the cost of debt securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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- References No definition available.
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- Definition Amount after adjustments of available-for-sale debt securities at cost, maturing in the next fiscal year following the latest fiscal year. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings less cumulative-effect adjustments, and fair value hedge accounting adjustments. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Fair value of available-for-sale debt securities maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of debt securities categorized neither as held-to-maturity nor trading. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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