Fair Value Measurements - Adjustments to the carrying value of investments (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Adjustments to the carrying value of these investments
Balance, beginning of period	$ 28,183	$ 26,988	$ 16,817	$ 22,844
Additional investments			11,000
Upward adjustments	234	122	679	6,006
Impairments and downward adjustments	(1,013)	(253)	(1,092)	(1,017)
Dispositions		(10,390)		(11,366)
Balance, end of period	27,404	$ 16,467	27,404	$ 16,467
Other Assets
Equity Securities without Readily Determinable Fair Value
Other equity investments	$ 59,200		$ 59,200		$ 54,000

Amount of equity investments other than securities.

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

+ References

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- Definition

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

+ References

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Amount of impairment loss and downward price adjustments on investment in equity security without readily determinable fair value.

+ References

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- Definition

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

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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 https://asc.fasb.org/extlink&oid=126980263&loc=SL75117539-209714

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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