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Goodwill and Other Intangibles - Changes in Goodwill (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Jun. 30, 2022	Dec. 31, 2024	Dec. 31, 2023
Goodwill [Roll Forward]
Goodwill, Beginning Balance		$ 5,079	$ 1,650
Goodwill resulted from the acquisition of Vivint			3,494
Impairment		(15)
Asset sales/Sale of Airtron			(69)
Foreign currency translation adjustments		(10)	4
Goodwill, Ending Balance		5,011	5,079
Airtron
Goodwill [Roll Forward]
Asset sales/Sale of Airtron		(43)
Texas
Goodwill [Roll Forward]
Goodwill, Beginning Balance		643	710
Goodwill resulted from the acquisition of Vivint		0
Impairment		0
Asset sales/Sale of Airtron			(67)
Foreign currency translation adjustments		0	0
Goodwill, Ending Balance		643	643
Texas \| Airtron
Goodwill [Roll Forward]
Asset sales/Sale of Airtron		0
East
Goodwill [Roll Forward]
Goodwill, Beginning Balance		721	723
Goodwill resulted from the acquisition of Vivint		0
Impairment	$ (130)	0
Asset sales/Sale of Airtron			(2)
Foreign currency translation adjustments		0	0
Goodwill, Ending Balance		721	721
East \| Airtron
Goodwill [Roll Forward]
Asset sales/Sale of Airtron		0
West/Services/Other
Goodwill [Roll Forward]
Goodwill, Beginning Balance		221	217
Goodwill resulted from the acquisition of Vivint		0
Impairment		(15)
Asset sales/Sale of Airtron			0
Foreign currency translation adjustments		(10)	4
Goodwill, Ending Balance		153	221
West/Services/Other \| Airtron
Goodwill [Roll Forward]
Asset sales/Sale of Airtron		(43)
Vivint Smart Home
Goodwill [Roll Forward]
Goodwill, Beginning Balance		3,494	0
Goodwill resulted from the acquisition of Vivint			3,494
Impairment		0
Asset sales/Sale of Airtron		0
Foreign currency translation adjustments		0
Goodwill, Ending Balance		3,494	$ 3,494
Vivint Smart Home \| Airtron
Goodwill [Roll Forward]
Asset sales/Sale of Airtron		$ 0