Severance and Exit Costs (Schedule of Severance and Exit Costs) (Details) - USD ($) $ in Millions		3 Months Ended
		Jun. 30, 2016	Jun. 30, 2015	Mar. 31, 2016
Restructuring Reserve [Roll Forward]
Restructuring Reserve		$ 436		$ 525
Supplemental Unemployment Benefits, Severance Benefits		94		150
Restructuring Charges		18
Severance Costs	[1]	4
Payments for Postemployment Benefits		(60)
Restructuring Reserve, Settled with Cash		(107)
Lease [Member]
Restructuring Reserve [Roll Forward]
Restructuring Reserve		310		338
Restructuring Charges	[2]	10
Restructuring reserved settled with cash and other adjustments		(38)
Access [Member]
Restructuring Reserve [Roll Forward]
Restructuring Reserve		32		$ 37
Restructuring reserved settled with cash and other adjustments		(9)
Wireless [Member] | Lease [Member]
Restructuring Reserve [Roll Forward]
Restructuring Charges	[3]	10
Wireless [Member] | Access [Member]
Restructuring Reserve [Roll Forward]
Restructuring Charges	[3]	4
Other Operating Income (Expense) [Member] | Wireless [Member]
Restructuring Reserve [Roll Forward]
Restructuring Reserve, Accrual Adjustment			$ 41
Successor [Member] | cost of products [Member] | Wireless [Member] | Access [Member]
Restructuring Reserve [Roll Forward]
Restructuring Charges		2
Successor [Member] | cost of products [Member] | Wireline [Member] | Access [Member]
Restructuring Reserve [Roll Forward]
Restructuring Charges		$ 2
Successor [Member] | Other Operating Income (Expense) [Member] | Wireless [Member]
Restructuring Reserve [Roll Forward]
Restructuring Reserve, Accrual Adjustment			$ 20

[1] For the three-month period ended June 30, 2016, we recognized costs of $4 million (Wireless only).

[2] For the three-month period ended June 30, 2016, we recognized costs of $10 million (Wireless only).

[3] For the three-month period ended June 30, 2016, $2 million (solely attributable to Wireline) was recognized as "Cost of services" and $2 million (solely attributable to Wireless) was recognized as "Severance and exit costs." We continually refine our network strategy and evaluate other potential network initiatives to improve the overall performance of our network. Additionally, a major cost reduction initiative is underway, which may include headcount reductions, among other actions, to reduce operating expenses and improve our operating cash flows. As a result of these ongoing activities, we may incur future material charges associated with lease and access exit costs, severance, asset impairments, and accelerated depreciation, among others.