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Discontinued Operations and Dispositions B2B Backup and Voice Asset Sales (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Jun. 30, 2021	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
(Loss) gain on sale of businesses		$ (21,798)	$ 17,122	$ 0
Goodwill impairment on business		32,629	$ 0	$ 0
Disposal Group, Held-for-sale, Not Discontinued Operations \| B2B Backup Business
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Goodwill impairment on business	$ 32,600
Disposal Group, Disposed of by Sale, Not Discontinued Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain (loss) on disposal		17,100
Disposal Group, Disposed of by Sale, Not Discontinued Operations \| Voice Assets
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
(Loss) gain on sale of businesses		2,800
Disposal Group, Disposed of by Sale, Not Discontinued Operations \| B2B Backup Business
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
(Loss) gain on sale of businesses		(24,600)
Goodwill impairment on business		$ 32,600