Segments - Schedule of Segment Reporting Information (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Segment Reporting Information [Line Items]
Total revenues and sales	$ 722.6	$ 292.2	$ 1,317.3	$ 873.6
Intersegment costs and expenses	(765.2)	(154.9)	(1,069.2)	(434.2)
Intersegment Eliminations
Segment Reporting Information [Line Items]
Total revenues and sales	32.3	0.0	32.3	0.0
Operating Segments
Segment Reporting Information [Line Items]
Total revenues and sales	754.9	292.2	1,349.6	873.6
Intersegment costs and expenses	(32.3)	0.0	(32.3)	0.0
Contribution margin	385.3	249.9	896.6	745.2
Total segment expenses	(337.3)	(42.3)	(420.7)	(128.4)
Kinetic
Segment Reporting Information [Line Items]
Total revenues and sales	360.3	0.0	360.3	0.0
Kinetic | Intersegment Eliminations
Segment Reporting Information [Line Items]
Total revenues and sales	7.9	0.0	7.9	0.0
Kinetic | Operating Segments
Segment Reporting Information [Line Items]
Total revenues and sales	368.2	0.0	368.2	0.0
Compensation expenses	(67.1)	0.0	(67.1)	0.0
Non-compensation managed expenses	(40.4)	0.0	(40.4)	0.0
Revenue-driven costs	(30.0)	0.0	(30.0)	0.0
Network access and facilities	(37.9)	0.0	(37.9)	0.0
Allocated network operations expenses	(10.6)	0.0	(10.6)	0.0
Customer access	(3.9)	0.0	(3.9)	0.0
Intersegment costs and expenses	(22.9)	0.0	(22.9)	0.0
Contribution margin	155.4	0.0	155.4	0.0
Uniti Solutions
Segment Reporting Information [Line Items]
Total revenues and sales	135.7	0.0	135.7	0.0
Uniti Solutions | Intersegment Eliminations
Segment Reporting Information [Line Items]
Total revenues and sales	0.9	0.0	0.9	0.0
Uniti Solutions | Operating Segments
Segment Reporting Information [Line Items]
Total revenues and sales	136.6	0.0	136.6	0.0
Compensation expenses	(6.5)	0.0	(6.5)	0.0
Non-compensation managed expenses	(0.4)	0.0	(0.4)	0.0
Revenue-driven costs	(20.4)	0.0	(20.4)	0.0
Customer access	(29.1)	0.0	(29.1)	0.0
Intersegment costs and expenses	(8.0)	0.0	(8.0)	0.0
Contribution margin	72.2	0.0	72.2	0.0
Fiber Infrastructure
Segment Reporting Information [Line Items]
Total revenues and sales	226.6	292.2	821.3	873.6
Fiber Infrastructure | Intersegment Eliminations
Segment Reporting Information [Line Items]
Total revenues and sales	23.5	0.0	23.5	0.0
Fiber Infrastructure | Operating Segments
Segment Reporting Information [Line Items]
Total revenues and sales	250.1	292.2	844.8	873.6
Compensation expenses	(18.0)	(12.2)	(42.0)	(35.7)
Non-compensation managed expenses	(4.8)	(3.2)	(12.1)	(10.0)
Revenue-driven costs	(15.2)	(4.1)	(23.3)	(13.3)
Network access and facilities	(48.5)	(22.8)	(92.5)	(69.4)
Allocated network operations expenses	(2.6)	0.0	(2.6)	0.0
Customer access	(1.9)	0.0	(1.9)	0.0
Intersegment costs and expenses	(1.4)	0.0	(1.4)	0.0
Contribution margin	157.7	249.9	669.0	745.2
Service revenues
Segment Reporting Information [Line Items]
Total revenues and sales	695.3	287.5	1,282.0	861.1
Service revenues | Kinetic
Segment Reporting Information [Line Items]
Total revenues and sales	348.6	0.0	348.6	0.0
Service revenues | Uniti Solutions
Segment Reporting Information [Line Items]
Total revenues and sales	135.3	0.0	135.3	0.0
Service revenues | Fiber Infrastructure
Segment Reporting Information [Line Items]
Total revenues and sales	211.4	287.5	798.1	861.1
Sales revenues
Segment Reporting Information [Line Items]
Total revenues and sales	27.3	4.7	35.3	12.5
Sales revenues | Kinetic
Segment Reporting Information [Line Items]
Total revenues and sales	11.7	0.0	11.7	0.0
Sales revenues | Uniti Solutions
Segment Reporting Information [Line Items]
Total revenues and sales	0.4	0.0	0.4	0.0
Sales revenues | Fiber Infrastructure
Segment Reporting Information [Line Items]
Total revenues and sales	$ 15.2	$ 4.7	$ 23.2	$ 12.5