Amount of investment in equity security without readily determinable fair value.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
-SubTopic 10
-Section 50
-Paragraph 3
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-URI http://asc.fasb.org/extlink&oid=120269885&loc=SL75117539-209714

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Amount of cumulative gain from upward price adjustment on investment in equity security without readily determinable fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=120269885&loc=SL75117539-209714

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Amount of impairment of investments in privately held companies.

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Investments - Investments in Privately-Held Companies (Details) - USD ($) $ in Millions	3 Months Ended			9 Months Ended
	Sep. 30, 2020	Mar. 31, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Investments in Privately-Held Companies and Investments in Equity Securities with Readily Determinable Fair Values
Impairments of investments in privately-held companies	$ 3.5	$ 5.6	$ 0.0	$ 9.1	$ 0.0
Privately-held Companies
Investments in Privately-Held Companies and Investments in Equity Securities with Readily Determinable Fair Values
Investments in privately-held companies	101.7			101.7		$ 86.0
Increase in the value of investment	$ 2.3	$ 22.5		$ 2.3