Short-term Investments	9 Months Ended
Sep. 30, 2020
Short Term Investments [Abstract]
Short-term Investments	(3) Short-term Investments As of September 30, 2020, the Company did not hold any short-term investment instruments. The amortized cost and fair value of available-for-sale investments at December 31, 2019 were $108.8 million and $108.9 million, respectively. The gross unrecognized holding gains accumulated in other comprehensive loss were not material as of December 31, 2019. As of December 31, 2019, none of the Company’s available-for-sale investments were in unrealized loss positions.

The entire disclosure for investments in certain debt and equity securities.

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