Investments - Schedule of Investment Maturity (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Investments, Debt and Equity Securities [Abstract]
Maturing in one year or less	$ 136,747
Maturing after one year through two years	0
Total debt investments	136,747	$ 105,386
Common stock of U.S. corporation	8
Total investments	$ 136,755

Available-For-Sale Securities, Debt Securities And Equity Securities, FV-NI

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- Definition

Available-for-sale Securities, Debt Maturities, Year Two, Fair Value

+ References

No definition available.

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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.

+ References

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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).

+ References

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- Definition

Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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