Summary Of Significant Accounting Policies (Narrative) (Details) customer in Millions, $ in Millions	6 Months Ended
	Jun. 30, 2025 USD ($) employee item segment state customer	Dec. 31, 2024 USD ($)
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Number of Reportable Segments | segment	1
Number of subscribers | customer	3.2
Number of states of operation | state	25
Annual support accepted for commitment for RDOF	$ 37
Number of employees | employee	12,800
Letter of credit issued, amount included in other assets	$ 55	$ 57
Restricted cash	152	161
Short-term Investments	$ 0
Revenue recognition period, FCC's CAF Phase II subsidies	7 years
Provided funding period, for construction of broadband networks	10 years
Remaining outstanding principal	$ 11,896	11,569
Number of stock plans | item	1
Securitization Trust Accounts [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Restricted cash, current	$ 93	56
Restricted cash, noncurrent	59	$ 105
US Treasuries In Trust Account [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Restricted cash	63
Debt On Frontier Southwest Properties [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Remaining outstanding principal	$ 47
Business And Wholesale [Member] | Minimum [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Useful life	11 years
Business And Wholesale [Member] | Maximum [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Useful life	16 years
Trademarks and Tradenames [Member]
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Useful life	5 years