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Summary of Significant Accounting Policies (Details) - USD ($) | 3 Months Ended
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Mar. 31, 2021 | Mar. 31, 2020
Summary of Significant Accounting Policies |  |
Impairment of intangible assets | $ 0 | $ 0
Impairment loss or recoveries | $ 0 | $ 0

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- References No definition available. + Details
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- Definition The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of an intangible asset (excluding goodwill) to fair value. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16373-109275 + Details
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- Definition Amount of impairment loss or recovery related to marketable securities. + References No definition available. + Details
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