Fair Value Measurements - Adjustments to the carrying value of investments (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021
Adjustments to the carrying value of these investments
Balance, beginning of period	$ 27,986	$ 22,905	$ 16,817	$ 22,844
Additional investments			11,000
Upward adjustments	231	5,763	445	5,884
Impairments and downward adjustments	(34)	(704)	(79)	(764)
Dispositions		(975)		(975)
Balance, end of period	28,183	$ 26,989	28,183	$ 26,989
Other Assets
Equity Securities without Readily Determinable Fair Value
Other equity investments	$ 62,200		$ 62,200		$ 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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Amount of dispositions adjustments on investment in equity security without readily determinable fair value.

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

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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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