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Investments (Summary of Securities without Readily Determinable Fair Value) (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2021 | Dec. 31, 2020
Investments, Debt and Equity Securities [Abstract] |  |
Cost | $ 31,779 | $ 50,384
Impairment | 0 | (19,605)
Adjustments | (479) | (479)
Reported Amount | $ 31,300 | $ 30,300

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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=120269885&loc=SL75117539-209714 + Details
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