Guarantor Financial Information (Condensed Consolidating Statement of Comprehensive Income (Loss) Information) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Revenues
Service revenues	$ 5,337	$ 4,005
Equipment sales	1,448	606
Other revenues	90	66
Total revenues	6,875	4,677
Operating expenses
Cost of services, exclusive of depreciation and amortization shown separately below	1,464	1,109
Cost of equipment sales	2,286	886
Selling, general and administrative	2,096	1,506
Depreciation and amortization	1,055	755
MetroPCS transaction and integration costs	12	13
Restructuring costs	0	31
Other, net	(10)	(2)
Total operating expenses	6,903	4,298
Operating income (loss)	(28)	379
Other income (expense)
Interest expense to affiliates	(18)	(178)
Interest expense	(276)	(51)
Interest income	75	35
Other expense, net	(6)	(6)
Total other expense, net	(225)	(200)
Income (loss) before income taxes	(253)	179
Income tax expense (benefit)	(102)	72
Earnings (loss) of subsidiaries	0	0
Net income (loss)	(151)	107
Other comprehensive loss, net of tax	(3)	(1)
Total comprehensive income (loss)	(154)	106
Consolidating and Eliminating Adjustments [Member]
Revenues
Service revenues	(78)	(26)
Equipment sales	(149)	(161)
Other revenues	(2)	(32)
Total revenues	(229)	(219)
Operating expenses
Cost of services, exclusive of depreciation and amortization shown separately below	0	(32)
Cost of equipment sales	(165)	(176)
Selling, general and administrative	(64)	(11)
Depreciation and amortization	0	0
MetroPCS transaction and integration costs	0	0
Restructuring costs		0
Other, net	0	0
Total operating expenses	(229)	(219)
Operating income (loss)	0	0
Other income (expense)
Interest expense to affiliates	0	0
Interest expense	0	0
Interest income	0	0
Other expense, net	0	0
Total other expense, net	0	0
Income (loss) before income taxes	0	0
Income tax expense (benefit)	0	0
Earnings (loss) of subsidiaries	77	(277)
Net income (loss)	77	(277)
Other comprehensive loss, net of tax	6	(1)
Total comprehensive income (loss)	83	(278)
Parent [Member]
Revenues
Service revenues	0	0
Equipment sales	0	0
Other revenues	0	0
Total revenues	0	0
Operating expenses
Cost of services, exclusive of depreciation and amortization shown separately below	0	0
Cost of equipment sales	0	0
Selling, general and administrative	0	0
Depreciation and amortization	0	0
MetroPCS transaction and integration costs	0	0
Restructuring costs		0
Other, net	0	0
Total operating expenses	0	0
Operating income (loss)	0	0
Other income (expense)
Interest expense to affiliates	0	0
Interest expense	0	0
Interest income	0	0
Other expense, net	0	0
Total other expense, net	0	0
Income (loss) before income taxes	0	0
Income tax expense (benefit)	0	0
Earnings (loss) of subsidiaries	(151)	0
Net income (loss)	(151)	0
Other comprehensive loss, net of tax	(3)	0
Total comprehensive income (loss)	(154)	0
Issuer [Member]
Revenues
Service revenues	0	0
Equipment sales	0	0
Other revenues	0	0
Total revenues	0	0
Operating expenses
Cost of services, exclusive of depreciation and amortization shown separately below	0	0
Cost of equipment sales	0	0
Selling, general and administrative	0	0
Depreciation and amortization	0	0
MetroPCS transaction and integration costs	0	0
Restructuring costs		0
Other, net	0	0
Total operating expenses	0	0
Operating income (loss)	0	0
Other income (expense)
Interest expense to affiliates	(18)	(178)
Interest expense	(214)	0
Interest income	0	0
Other expense, net	(8)	(6)
Total other expense, net	(240)	(184)
Income (loss) before income taxes	(240)	(184)
Income tax expense (benefit)	0	0
Earnings (loss) of subsidiaries	89	291
Net income (loss)	(151)	107
Other comprehensive loss, net of tax	(3)	(1)
Total comprehensive income (loss)	(154)	106
Guarantor Subsidiaries [Member]
Revenues
Service revenues	5,150	3,855
Equipment sales	1,597	767
Other revenues	58	56
Total revenues	6,805	4,678
Operating expenses
Cost of services, exclusive of depreciation and amortization shown separately below	1,460	1,122
Cost of equipment sales	2,313	932
Selling, general and administrative	2,060	1,481
Depreciation and amortization	1,035	735
MetroPCS transaction and integration costs	12	13
Restructuring costs		31
Other, net	(10)	(2)
Total operating expenses	6,870	4,312
Operating income (loss)	(65)	366
Other income (expense)
Interest expense to affiliates	0	0
Interest expense	(18)	(8)
Interest income	75	35
Other expense, net	2	0
Total other expense, net	59	27
Income (loss) before income taxes	(6)	393
Income tax expense (benefit)	(100)	81
Earnings (loss) of subsidiaries	(15)	(14)
Net income (loss)	79	298
Other comprehensive loss, net of tax	(3)	1
Total comprehensive income (loss)	76	299
Non-Guarantor Subsidiaries [Member]
Revenues
Service revenues	265	176
Equipment sales	0	0
Other revenues	34	42
Total revenues	299	218
Operating expenses
Cost of services, exclusive of depreciation and amortization shown separately below	4	19
Cost of equipment sales	138	130
Selling, general and administrative	100	36
Depreciation and amortization	20	20
MetroPCS transaction and integration costs	0	0
Restructuring costs		0
Other, net	0	0
Total operating expenses	262	205
Operating income (loss)	37	13
Other income (expense)
Interest expense to affiliates	0	0
Interest expense	(44)	(43)
Interest income	0	0
Other expense, net	0	0
Total other expense, net	(44)	(43)
Income (loss) before income taxes	(7)	(30)
Income tax expense (benefit)	(2)	(9)
Earnings (loss) of subsidiaries	0	0
Net income (loss)	(5)	(21)
Other comprehensive loss, net of tax	0	0
Total comprehensive income (loss)	$ (5)	$ (21)