Segment Information (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013
Segment Reporting, Revenue Reconciling Item [Line Items]
Assets	$ 13,983		$ 13,983		$ 12,874
Payments to Acquire Productive Assets	204	194	608	571
Adjusted EBITDA by Segment	471	385	1,388	1,158
Revenue	1,629	1,569	4,863	4,711
Income Tax Expense (Benefit)	(8)	(14)	(27)	(39)
Other Income	(169)	(159)	(507)	(531)
Depreciation, Depletion and Amortization	(187)	(203)	(558)	(596)
Share-based Compensation	(22)	(30)	(48)	(115)
Net Income (Loss) Available to Common Stockholders, Basic	85	(21)	248	(123)
Corporate and Other [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Assets	262		262		266
Payments to Acquire Productive Assets	19	21	102	76
Adjusted EBITDA by Segment	(170)	(195)	(503)	(548)
North America [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Assets	9,321		9,321		8,133
Payments to Acquire Productive Assets	116	105	318	305
Adjusted EBITDA by Segment	492	447	1,460	1,309
Europe [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Assets	1,963		1,963		2,030
Payments to Acquire Productive Assets	34	33	82	102
Adjusted EBITDA by Segment	57	56	167	171
Latin America [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Assets	2,437		2,437		2,445
Payments to Acquire Productive Assets	35	35	106	88
Adjusted EBITDA by Segment	92	77	264	226
Core Network Service [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue	1,482	1,397	4,418	4,148
Core Network Service [Member] | North America [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue	1,063	987	3,157	2,924
Core Network Service [Member] | Europe [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue	219	222	673	665
Core Network Service [Member] | Latin America [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue	200	188	588	559
Wholesale Voice Services and Other [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue	147	172	445	563
Wholesale Voice Services and Other [Member] | North America [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue	128	162	410	530
Wholesale Voice Services and Other [Member] | Europe [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue	4	8	14	25
Wholesale Voice Services and Other [Member] | Latin America [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue	$ 15	$ 2	$ 21	$ 8