Fair Value Measurements - Adjustments to the carrying value of investments (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Adjustments to the carrying value of these investments
Balance, beginning of year	$ 19,771	$ 20,376
Upward adjustments	106	101
Impairments and downward adjustments	(789)
Balance, end of year	19,088	$ 20,477
Other Assets
Equity Securities without Readily Determinable Fair Value
Other equity investments	$ 34,900		$ 36,600

Amount of equity investments other than securities.

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- Definition

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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- 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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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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