Wireless Licenses, Goodwill and Other Intangible Assets (Tables)

9 Months Ended

Sep. 30, 2018

Goodwill and Intangible Assets Disclosure [Abstract]

Carrying Amount of Wireless Licenses

The carrying amount of Wireless licenses are as follows:

	At September 30,		At December 31,
(dollars in millions)	2018		2017
Wireless licenses	$	94,006	$	88,417

Changes in Carrying Amount of Goodwill

Changes in the carrying amount of Goodwill are as follows:

(dollars in millions)	Wireless		Wireline			Other			Total
Balance at January 1, 2018	$	18,397	$	3,955		$	6,820		$	29,172
Acquisitions (Note 3)	—		(82		)	225			143
Reclassifications, adjustments and other	—		(4		)	(111		)	(115		)
Balance at September 30, 2018	$	18,397	$	3,869		$	6,934		$	29,200

Composition of Other Intangible Assets, Net

The following table displays the composition of Other intangible assets, net:

	At September 30, 2018							At December 31, 2017
(dollars in millions)	Gross Amount		Accumulated Amortization			Net Amount		Gross Amount		Accumulated Amortization			Net Amount
Customer lists (8 to 13 years)	$	3,623	$	(945	)	$	2,678	$	3,621	$	(691	)	$	2,930
Non-network internal-use software (3 to 7 years)	18,901		(13,371		)	5,530		18,010		(12,374		)	5,636
Other (2 to 25 years)	2,484		(961		)	1,523		2,474		(793		)	1,681
Total	$	25,008	$	(15,277	)	$	9,731	$	24,105	$	(13,858	)	$	10,247

Amortization Expense for Other Intangible Assets

The amortization expense for Other intangible assets was as follows: 

	Three Months Ended		Nine Months Ended
(dollars in millions)	September 30,		September 30,
2018	$	557	$	1,648
2017	536		1,473

Estimated Future Amortization Expense for Other Intangible Assets

The estimated future amortization expense for Other intangible assets is as follows:

Years	(dollars in millions)
Remainder of 2018	$	557
2019	2,027
2020	1,692
2021	1,400
2022	1,149
2023	871