Short-term Investments	6 Months Ended
Jun. 30, 2020
Short Term Investments [Abstract]
Short-term Investments	(3) Short-term Investments The amortized cost and fair value of available-for-sale investments at June 30, 2020 were $109.6 million and $110.0 million, respectively. 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 June 30, 2020 and December 31, 2019. As of June 30, 2020 and 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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