Fair Value Measurements Equity Securities Without Readily Determinable Fair Values (Details) $ in Thousands	9 Months Ended
Sep. 30, 2021 USD ($)
Equity Securities Without Readily Determinable Fair Value Amount [Roll Forward]
Carrying value as of December 31, 2020	$ 13,000
Additions	552
Equity Securities without Readily Determinable Fair Value, Sales, Annual Amount	(33)
Equity Securities without Readily Determinable Fair Value, Donations, Annual Amount	(134)
Carrying value as of September 30, 2021	14,000
Fair Value, Inputs, Level 3
Equity Securities Without Readily Determinable Fair Value Amount [Roll Forward]
Carrying value as of December 31, 2020	13,444
Carrying value as of September 30, 2021	13,830
Cumulative upward carrying value changes between January 1, 2018 and September 30, 2021	13,444
Cumulative downward carrying value changes/impairment between January 1, 2018 and September 30, 2021	$ 0

Equity Securities without Readily Determinable Fair Value, Additions, Annual Amount

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

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Equity Securities without Readily Determinable Fair Value, Donations, Annual Amount

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Equity Securities without Readily Determinable Fair Value, Sales, Annual Amount

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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=123583765&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=123583765&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=123583765&loc=SL75117539-209714

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