Investments (Gain (Loss) on Marketable Equity Securities) (Details 2) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Investments [Abstract]
(Loss) gain on marketable equity securities, net	$ (100,393)	$ 24,066
Less: Net losses (gains) in earnings from marketable equity securities sold and donated	8,774	(2,982)
Net unrealized (losses) gains in earnings from marketable equity securities still held at the end of the period	$ (91,619)	$ 21,084

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).

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=116654751&loc=SL75117546-209714

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

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

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