Goodwill - Narrative (Details)	3 Months Ended	12 Months Ended
Mar. 31, 2021 USD ($) segment	Mar. 31, 2020 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Goodwill [Line Items]
Goodwill	$ 7,367,000		$ 7,367,000	$ 7,908,000
Number of reporting units \| segment	2
Impairment charges - goodwill	$ 0	$ 541,000	541,000
Oblong Industries
Goodwill [Line Items]
Goodwill	7,367,000		7,367,000	7,367,000
Impairment charges - goodwill	0		0
Oblong (formerly Glowpoint)
Goodwill [Line Items]
Goodwill	$ 0		0	$ 541,000
Impairment charges - goodwill		$ 541,000	$ 541,000

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Name:	us-gaap_GoodwillImpairmentLoss
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration