Investment and Other Income (Loss), Net (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Investments, Debt and Equity Securities [Abstract]
Gain (loss) on equity securities	$ 0	$ (5,690)	$ 11,604	$ (10,258)
Investment and other income, net	1,223	3,561	6,347	7,909
Total investment and other income (loss), net	$ 1,223	$ (2,129)	$ 17,951	$ (2,349)

Equity Securities, Fv-Ni, Gain (Loss) And Investment Income, Net

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- Definition

Amount of unrealized and realized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=120269885&loc=SL75117546-209714

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Amount after accretion (amortization) of discount (premium), and investment expense, of interest income and dividend income on nonoperating securities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.7(a),(b))
-URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.8)
-URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227

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