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Debt instrument maturity year.

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Incremental stock based compensation expense.

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Preferred stock redemption preference value.

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Preferred stock redemption price percentage.

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Price of a single share of a number of saleable stocks paid or offered to be paid in a business combination.

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Mergers and Acquisitions - Narrative (Details)					1 Months Ended	2 Months Ended	3 Months Ended	8 Months Ended	9 Months Ended	12 Months Ended	20 Months Ended
Mergers and Acquisitions - Narrative (Details)	Sep. 22, 2021 USD ($) $ / shares	Sep. 07, 2021 USD ($) $ / shares	Aug. 31, 2021 USD ($) mi	Mar. 13, 2020 USD ($)	Sep. 30, 2021 USD ($)	Sep. 07, 2021 USD ($) $ / shares	Sep. 30, 2020 USD ($)	Sep. 07, 2021 USD ($) $ / shares	Sep. 30, 2020 USD ($)	Dec. 31, 2020 USD ($)	Sep. 07, 2021 USD ($) $ / shares	Sep. 08, 2021 USD ($)
Business Acquisition [Line Items]
Gross value of acquisition					$ 1,620,700,000			$ 0	$ 0
Preferred Stock, Dividend Rate, Percentage										6.75%
Transaction and integration costs					0	$ 51,500,000	$ 2,200,000	54,800,000	33,800,000
Loss on extinguishment of debt					0	$ (10,700,000)	$ 0	$ (10,700,000)	0
Funded to escrow account					0					$ 5,000,000.0
Red Fiber Parent LLC [Member]
Business Acquisition [Line Items]
Gross value of acquisition		$ 3,100,000,000
Debt assumed		$ 1,357,100,000
Common shares price per share as stock consideration \| $ / shares		$ 15.50				$ 15.50		$ 15.50			$ 15.50
Preferred stock redemption percentage	6.75%
Preferred stock redemption price per Depositary Share \| $ / shares	$ 50
Preferred stock redemption preference per redemption percentage	$ 1,000
Preferred Stock, Dividend Rate, Percentage	6.75%
Cumulative transaction costs					$ 0			$ 54,600,000	$ 8,700,000		$ 64,400,000
Transaction and integration costs		$ 44,000,000.0
Severance Costs								2,900,000
Transaction-related bonuses								5,300,000
Loss on extinguishment of debt								10,700,000
Red Fiber Parent LLC [Member] \| New Credit Agreement and Term Loan Due 2028 [Member]
Business Acquisition [Line Items]
Note issuance costs capitalized												$ 32,000,000.0
Debt instrument maturity year					2028
Red Fiber Parent LLC [Member] \| Revolving Credit Facility Due 2026 [Member]
Business Acquisition [Line Items]
Note issuance costs capitalized												$ 6,100,000
Debt instrument maturity year					2026
Red Fiber Parent LLC [Member] \| SG&A [Member]
Business Acquisition [Line Items]
Incremental stock-based compensation expense								$ 9,300,000
Brookfield Infrastructure Group [Member]
Business Acquisition [Line Items]
Termination fee				$ 24,800,000
Paniolo Acquisition [Member]
Business Acquisition [Line Items]
Gross value of acquisition			$ 29,300,000
Aggregate purchase price			52,300,000
Business combination committed purchase money financing			$ 23,000,000.0
Current portion of long-term debt					$ 500,000
Long-term debt, less current portion					$ 22,400,000
Funded to escrow account										$ 5,000,000.0
Paniolo Acquisition [Member] \| Minimum [Member]
Business Acquisition [Line Items]
Fiber route miles \| mi			400