Investments - Held to Maturity Investments (Details) $ in Millions	Sep. 30, 2018 USD ($)
Amortized Cost
Due in one year or less	$ 111
Due after one year through five years	7
Debt Securities, Held-to-maturity	118
Estimated Fair Value
Due in one year or less	111
Due after one year through five years	7
Estimated Fair Value, Total	$ 118

Amount of investment in debt security measured at amortized cost (held-to-maturity).

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
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+ References

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-SubTopic 10
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+ References

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