Property, Plant And Equipment (Tables)

12 Months Ended

Dec. 31, 2017

Property, Plant And Equipment [Abstract]

Property, Plant And Equipment, Net

($ in millions)	Estimated Useful Lives	2017		2016
Land	N/A	$	231	$	235
Buildings and leasehold improvements	41 years		2,282		2,320
General support	5 to 17 years		1,570		1,502
Central office/electronic circuit equipment	5 to 18 years		8,137		7,683
Poles	30 years		1,095		995
Cable, fiber and wire	15 to 25 years		10,997		10,292
Conduit	55 years		1,646		1,611
Construction work in progress			538		903
Property, plant and equipment			26,496		25,541
Less: Accumulated depreciation			(12,119)		(10,639)
Property, plant and equipment, net		$	14,377	$	14,902

Schedule Of Depreciation Expense

	For the Year Ended
($ in millions)	2017		2016		2015
Depreciation expense	$	1,485	$	1,388	$	983