Description of Business and Accounting Policies - Narrative (Details)		4 Months Ended	8 Months Ended	12 Months Ended
	Sep. 07, 2021 USD ($) $ / shares	Dec. 31, 2021 USD ($) Customer	Sep. 07, 2021 USD ($) $ / shares	Dec. 31, 2021 USD ($) Customer shares	Dec. 31, 2020 USD ($) Customer	Dec. 31, 2019 USD ($)
Description of Business and Accounting Policies [Line Items]
Entity number of employees		5,200		5,200
Company employees participating in collective bargaining agreement, percentage		22.00%		22.00%
Trade receivables due from customers, range, minimum				21 days
Trade receivables due from customers, range, maximum				90 days
Unbilled receivables, current		$ 70,800,000		$ 70,800,000	$ 41,000,000.0
Allowance for uncollectible accounts		3,600,000		3,600,000	23,000,000.0
Accounts receivable sold				0	0
Goodwill, impairment loss		0	$ 0		0	$ 0
Impairment losses on Indefinite-lived intangible assets		0	0		0	0
Impairment loss on long-lived assets		0	0	0	0	0
Cost method investments		7,000,000.0		$ 7,000,000.0	6,900,000
Impairment losses on cost method investments		$ 0	$ 0		$ 0	$ 0
Revenue derived from foreign operations		6.00%	6.00%		5.00%	5.00%
Service delivery period, indefeasible right of use contracts, upper range, in years				25 years
Customer contract, maintenance on telephony equipment, lower range, in years				1 year
Customer contract, maintenance on telephony equipment, upper range, in years				3 years
Restructuring liabilities included in other current liabilities		$ 200,000		$ 200,000	$ 4,500,000
Advertising expense		7,100,000	$ 12,800,000		15,600,000	$ 18,600,000
Regulatory taxes included in revenue		13,200,000	27,200,000		32,200,000	29,200,000
Regulatory taxes included in expense		$ 13,700,000	$ 32,100,000		$ 34,200,000	$ 32,500,000
2017 Stock Plan for Non-Employee Directors
Description of Business and Accounting Policies [Line Items]
Number of outstanding awards granted | shares				0
Hawaiian Telcom 2010 Equity Incentive Plan
Description of Business and Accounting Policies [Line Items]
Number of outstanding awards granted | shares				0
Cincinnati Bell Incorporation
Description of Business and Accounting Policies [Line Items]
Business Acquisition, Share Price | $ / shares	$ 15.50		$ 15.50
Cincinnati Bell Incorporation | SG&A [Member]
Description of Business and Accounting Policies [Line Items]
Incremental stock-based compensation expense	$ 9,300,000		$ 9,300,000
Cincinnati Bell Incorporation | SG&A [Member] | 2017 Long-Term Incentive Plan
Description of Business and Accounting Policies [Line Items]
Number of outstanding awards granted | shares				0
Verizon Communications Inc. [Member]
Description of Business and Accounting Policies [Line Items]
Number of customers, exceeds 10% of total accounts receivable | Customer		1		1	1
Accounts receivable from one customer greater than 10%, percentage		26.00%		26.00%	20.00%