Commitments and Contingencies - Narrative (Details)	2 Months Ended	3 Months Ended	12 Months Ended
	Sep. 07, 2021 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2023 USD ($) RenewalOption	Dec. 31, 2022 USD ($)
Commitments And Contingencies [Line Items]
Other current liabilities		$ 62,800,000	$ 62,800,000	$ 47,800,000
Other noncurrent liabilities		143,200,000	143,200,000	119,400,000
Jointly Owned Utility Plant Aggregate Construction Cost		235,000,000.0	235,000,000.0
Amount paid for dedicated fiber build			$ 16,300,000	2,200,000
Up-Front Payments For Services, Upper Range, Years			25 years
Proceeds from sale of capacity, recorded in other noncurrent liabilities		18,800,000	$ 18,800,000	18,100,000
Proceeds from sale of capacity, recorded in other current liabilities		1,600,000	1,600,000	1,400,000
Liability for services to be delivered related to up-front payment received current		72,000,000	72,000,000	81,600,000
Letters of Credit Outstanding, Amount		17,200,000	17,200,000
Indemnification liability		0	0	0
Other Current Liabilities [Member]
Commitments And Contingencies [Line Items]
Liability for services to be delivered related to up-front payment received current		4,100,000	4,100,000	200,000
Other Noncurrent Liabilities [Member]
Commitments And Contingencies [Line Items]
Liability for services to be delivered related to up-front payment received non current		79,500,000	$ 79,500,000	200,000
Maximum [Member]
Commitments And Contingencies [Line Items]
SEA-US contract term			25 years
Indefeasible right of use of contract term			25 years
Long-term Purchase Commitments, Period			3 years
Minimum [Member]
Commitments And Contingencies [Line Items]
SEA-US contract term			15 years
Indefeasible right of use of contract term			15 years
Long-term Purchase Commitments, Period			1 year
Pole license agreement obligation [Member]
Commitments And Contingencies [Line Items]
Contract Term, in Years			10 years
Number of renewal options | RenewalOption			2
Renewal option term			5 years
Financing obligation remeasured and includes fair value step up	$ 12,200,000
Other installment financing arrangements		43,600,000	$ 43,600,000	46,600,000
Other current liabilities		2,800,000	$ 2,800,000	3,000,000
Data Center Financing Arrangements [Member]
Commitments And Contingencies [Line Items]
Contract Term, in Years			10 years
Number of renewal options | RenewalOption			2
Renewal option term			2 years
Financing obligation remeasured and includes fair value step up	$ 700,000
Other installment financing arrangements		3,000,000	$ 3,000,000	3,500,000
Other current liabilities		600,000	600,000	600,000
Other noncurrent liabilities		2,400,000	$ 2,400,000	2,900,000
Dedicated Fiber Agreement [Member]
Commitments And Contingencies [Line Items]
Indefeasible right of use of contract term	20 years		20 years
Liability for services to be delivered related to up-front payment received		58,600,000	$ 58,600,000	52,900,000
Dedicated Fiber Agreement [Member] | Other Current Liabilities [Member]
Commitments And Contingencies [Line Items]
Liability for services to be delivered related to up-front payment received current		2,100,000	2,100,000	1,400,000
Dedicated Fiber Agreement [Member] | Other Noncurrent Liabilities [Member]
Commitments And Contingencies [Line Items]
Liability for services to be delivered related to up-front payment received non current		56,500,000	56,500,000	$ 51,500,000
Involuntary Events and Contingencies [Member]
Commitments And Contingencies [Line Items]
Other current liabilities		2,000,000	2,000,000
Other noncurrent liabilities		2,000,000	2,000,000
General insurance liability		4,000,000	4,000,000
Legal expense			1,100,000
Involuntary Events and Contingencies [Member] | Other Noncurrent Assets [Member]
Commitments And Contingencies [Line Items]
Offsetting receivable		2,000,000	$ 2,000,000
Involuntary Events and Contingencies [Member] | Accounts Payable [Member]
Commitments And Contingencies [Line Items]
Insurance voluntary fund		$ 2,500,000