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Summary of Significant Accounting Policies (Details) - USD ($)	3 Months Ended
	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.

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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

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- Definition

Amount of impairment loss or recovery related to marketable securities.

+ References

No definition available.

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