Basis of Presentation and Summary of Significant Accounting Policies - Narrative (Details)		3 Months Ended			9 Months Ended
	May 03, 2024 shares	Sep. 30, 2025 USD ($) $ / shares	Mar. 31, 2025 USD ($) shares	Sep. 30, 2024 USD ($) $ / shares	Sep. 30, 2025 USD ($) $ / shares	Sep. 30, 2024 USD ($) $ / shares shares	Aug. 01, 2025 director	Dec. 31, 2024 USD ($)	Jan. 31, 2024 USD ($)
Summary Of Significant Accounting Policies [Line Items]
Number of board of directors appointed | director							9
Net income attributable to shareholders		$ 1,608,900,000		$ 12,200,000	$ 1,610,400,000	$ 71,800,000
Basic (in dollars per share) | $ / shares		$ 7.26		$ 0.08	$ 9.29	$ 0.49
Diluted (in dollars per share) | $ / shares		$ 4.92		$ 0.08	$ 7.21	$ 0.49
Prepaid expenses		$ (104,000,000.0)			$ (104,000,000.0)			$ (16,200,000)
Other current assets		(193,000,000.0)			(193,000,000.0)			(18,100,000)
Accounts receivable, net		(345,300,000)			(345,300,000)			(51,500,000)
Operating lease income		124,500,000		$ 230,900,000	597,000,000.0	$ 688,400,000
Sales revenue		13,600,000		3,000,000.0	16,300,000	3,000,000.0
Cost of sales		7,800,000		100,000	8,400,000	100,000
Gross profit		5,800,000		$ 2,900,000	7,900,000	$ 2,900,000
Grants receivable		$ 107,500,000			$ 107,500,000			0
OP Unit Conversion Ratio		1			1
Cash Share Exchange
Summary Of Significant Accounting Policies [Line Items]
Exchange of noncontrolling interest (in shares) | shares			14,722			68,384
Cash Share Purchase
Summary Of Significant Accounting Policies [Line Items]
Exchange of noncontrolling interest (in shares) | shares						14,722
Exchange of noncontrolling interest			$ 100,000			$ 100,000
Old Uniti
Summary Of Significant Accounting Policies [Line Items]
Number of board of directors appointed | director							5
Old Uniti | Old Uniti
Summary Of Significant Accounting Policies [Line Items]
Percentage voting interest acquired							62.00%
Macquarie Asset Management | Disposal Group, Held-for-Sale, Not Discontinued Operations | CableSouth Transaction
Summary Of Significant Accounting Policies [Line Items]
Cash consideration									$ 40,000,000.0
Pretax gain from sale						$ 19,000,000.0
Spectrum licenses
Summary Of Significant Accounting Policies [Line Items]
Initial term		10 years			10 years
Revision of Prior Period, Reclassification, Adjustment
Summary Of Significant Accounting Policies [Line Items]
Prepaid expenses								16,200,000
Other current assets								18,100,000
Accounts receivable, net								108,900,000
Accounts receivable, net of current portion								10,500,000
Accounts receivable, net of non-current portion								98,400,000
Accounts payable								13,600,000
Accrued taxes								7,100,000
Settlement payable								71,800,000
Dividends payable								600,000
Current portion of finance lease obligations								2,700,000
Accounts payable, accrued expenses and other liabilities, current								43,800,000
Intangibles liabilities, net								145,700,000
Finance lease obligations								14,500,000
Accounts payable, accrued expenses and other liabilities, non-current								$ 25,200,000
Change in Accounting Method Accounted for as Change in Estimate
Summary Of Significant Accounting Policies [Line Items]
Depreciation expense		$ 7,100,000
Net income attributable to shareholders		$ 6,400,000
Basic (in dollars per share) | $ / shares		$ 0.03
Diluted (in dollars per share) | $ / shares		$ 0.02
Common Stock
Summary Of Significant Accounting Policies [Line Items]
Exchange of noncontrolling interest (in shares) | shares	0.6029
Common Stock | Cash Share Exchange
Summary Of Significant Accounting Policies [Line Items]
Exchange of noncontrolling interest (in shares) | shares						53,662