ASC 606 Adoption And Revenue Recognition (Disaggregation Of Revenue) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers									$ 8,228	$ 8,352	$ 8,099
Subsidy and other regulatory revenue									383	776	797
Total revenue	$ 2,124	$ 2,126	$ 2,162	$ 2,199	$ 2,217	$ 2,251	$ 2,304	$ 2,356	8,611	9,128	8,896
Frontier Secure Strategic Partnerships [Member]
Disaggregation of Revenue [Line Items]
Total revenue										40	84
Data And Internet Services [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers									3,878	3,862	3,693
Voice Services [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers									2,721	2,864	2,886
Video Services [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers									1,085	1,304	1,244
Other [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers									544	322	276
Consumer [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers									4,380	4,476	4,383
Commercial [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers									3,848	$ 3,876	$ 3,716
Impact Of Adoption Of ACS 606 [Member] | Accounting Standards Update 2014-09 [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers									(349)
Subsidy and other regulatory revenue									334
Total revenue									(15)
Impact Of Adoption Of ACS 606 [Member] | Data And Internet Services [Member] | Accounting Standards Update 2014-09 [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers									(103)
Impact Of Adoption Of ACS 606 [Member] | Voice Services [Member] | Accounting Standards Update 2014-09 [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers									(152)
Impact Of Adoption Of ACS 606 [Member] | Video Services [Member] | Accounting Standards Update 2014-09 [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers									99
Impact Of Adoption Of ACS 606 [Member] | Other [Member] | Accounting Standards Update 2014-09 [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers									(193)
Impact Of Adoption Of ACS 606 [Member] | Consumer [Member] | Accounting Standards Update 2014-09 [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers									(116)
Impact Of Adoption Of ACS 606 [Member] | Commercial [Member] | Accounting Standards Update 2014-09 [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers									(233)
Amounts Excluding Adoption of ASC 606 [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers									7,879
Subsidy and other regulatory revenue									717
Total revenue									8,596
Amounts Excluding Adoption of ASC 606 [Member] | Data And Internet Services [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers									3,775
Amounts Excluding Adoption of ASC 606 [Member] | Voice Services [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers									2,569
Amounts Excluding Adoption of ASC 606 [Member] | Video Services [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers									1,184
Amounts Excluding Adoption of ASC 606 [Member] | Other [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers									351
Amounts Excluding Adoption of ASC 606 [Member] | Consumer [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers									4,264
Amounts Excluding Adoption of ASC 606 [Member] | Commercial [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers									$ 3,615