Balance Sheet Components (Schedule of Changes in Carrying Value of Long-term Investments) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Balance Sheet Related Disclosures [Abstract]
Beginning Balance	$ 8,147	$ 2,886
Additions	5,850	5,484
Downward adjustments for observable price changes		(223)
Impairment and downward adjustments for observable price changes	(6,239)
Ending Balance	$ 7,758	$ 8,147

Equity securities without readily determinable fair value amount additions.

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- References

No definition available.

+ Details

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- Definition

Amount of 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 (a)
-URI http://asc.fasb.org/extlink&oid=120269885&loc=SL75117539-209714

+ Details

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- Definition

Amount of loss from downward 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 (b)
-URI http://asc.fasb.org/extlink&oid=120269885&loc=SL75117539-209714

+ Details

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- Definition

Amount of impairment loss 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 (b)
-URI http://asc.fasb.org/extlink&oid=120269885&loc=SL75117539-209714

+ Details

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