Fair Value Measurements Equity Securities Without Readily Determinable Fair Values (Details) $ in Thousands	3 Months Ended
Mar. 31, 2020 USD ($)
Equity Securities Without Readily Determinable Fair Value Amount [Roll Forward]
Carrying value as of December 31, 2019	$ 13,000
Carrying value as of March 31, 2020	13,000
Fair Value, Inputs, Level 3
Equity Securities Without Readily Determinable Fair Value Amount [Roll Forward]
Carrying value as of December 31, 2019	13,444
Carrying value changes	0
Carrying value as of March 31, 2020	13,444
Cumulative upward carrying value changes between January 1, 2018 and March 31, 2020	13,444
Cumulative downward carrying value changes/impairment between January 1, 2018 and March 31, 2020	$ 0

Equity Securities Without Readily Determinable Fair Value Amount [Roll Forward]

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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=116654751&loc=SL75117539-209714

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- Definition

Amount of cumulative 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=116654751&loc=SL75117539-209714

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- Definition

Amount of 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=116654751&loc=SL75117539-209714

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- Definition

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=116654751&loc=SL75117539-209714

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