Guarantor Financial Information (CONDENSED CONSOLIDATING BALANCE SHEET) (Details) - USD ($) $ in Millions		Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2013	Mar. 31, 2013	Dec. 31, 2012	[2]
Current assets
Short-term investments		$ 0	$ 166
Accounts and notes receivable, net		1,099	2,290
Device and accessory inventory		1,173	1,359
Current deferred tax asset		0	62
Prepaid expenses and other current assets		1,920	1,890
Total Current Assets		6,833	9,777
Property, plant and equipment, net		20,297	19,721
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill		6,575	6,575
FCC licenses and other		40,073	39,987
Definite-lived intangible assets, net		4,469	5,893
Other assets		728	888
Total assets		78,975	82,841
Current liabilities
Accounts payable	[1]	2,899	4,347
Accrued expenses and other current liabilities		4,374	5,293
Current portion of long-term debt, financing and capital lease obligations		4,690	1,300
Total Current Liabilities		11,963	10,940
Long-term debt, financing and capital lease obligations		29,268	32,342
Deferred tax liabilities		13,959	13,898
Other liabilities		4,002	3,951
Total liabilities		$ 59,192	$ 61,131
Commitments and contingencies
Total Stockholders' Equity		$ 19,783	$ 21,710
Total Liabilities and Stockholders' equity		78,975	82,841
Successor [Member]
Current assets
Short-term investments			166
Accounts and notes receivable, net		1,099	2,290
Device and accessory inventory		1,173	1,359
Current deferred tax asset			62
Prepaid expenses and other current assets		1,920	1,890
Total Current Assets		6,833	9,777
Investment in subsidiaries		0	0
Property, plant and equipment, net		20,297	19,721
Due from consolidated affiliate		0	0
Note receivable from consolidated affiliate		0	0
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill		6,575	6,575	$ 6,383
FCC licenses and other		40,073	39,987
Definite-lived intangible assets, net		4,469	5,893
Other assets		728	888
Total assets		78,975	82,841	84,549	$ 85,953	$ 3,122
Current liabilities
Accounts payable		2,899	4,347
Accrued expenses and other current liabilities		4,374	5,293
Current portion of long-term debt, financing and capital lease obligations		4,690	1,300
Total Current Liabilities		11,963	10,940
Long-term debt, financing and capital lease obligations		29,268	32,342
Deferred tax liabilities		13,959	13,898
Note due to consolidated affiliate		0	0
Other liabilities		4,002	3,951
Due to consolidated affiliate		0	0
Total liabilities		59,192	61,131
Total Stockholders' Equity		19,783	21,710	$ 25,312	$ 25,584		$ 3,110
Total Liabilities and Stockholders' equity		78,975	82,841
Successor [Member] | Parent [Member]
Current assets
Short-term investments			0
Accounts and notes receivable, net		87	84
Device and accessory inventory		0	0
Current deferred tax asset			0
Prepaid expenses and other current assets		0	0
Total Current Assets		87	84
Investment in subsidiaries		19,783	21,712
Property, plant and equipment, net		0	0
Due from consolidated affiliate		50	68
Note receivable from consolidated affiliate		10,377	10,361
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill		0	0
FCC licenses and other		0	0
Definite-lived intangible assets, net		0	0
Other assets		0	0
Total assets		30,297	32,225
Current liabilities
Accounts payable		0	0
Accrued expenses and other current liabilities		137	154
Current portion of long-term debt, financing and capital lease obligations		0	0
Total Current Liabilities		137	154
Long-term debt, financing and capital lease obligations		10,377	10,361
Deferred tax liabilities		0	0
Note due to consolidated affiliate		0	0
Other liabilities		0	0
Due to consolidated affiliate		0	0
Total liabilities		10,514	10,515
Total Stockholders' Equity		19,783	21,710
Total Liabilities and Stockholders' equity		30,297	32,225
Successor [Member] | Guarantor Subsidiaries [Member]
Current assets
Short-term investments			146
Accounts and notes receivable, net		27	157
Device and accessory inventory		0	0
Current deferred tax asset			0
Prepaid expenses and other current assets		12	13
Total Current Assets		2,193	3,808
Investment in subsidiaries		23,129	22,413
Property, plant and equipment, net		0	0
Due from consolidated affiliate		19,518	20,934
Note receivable from consolidated affiliate		245	458
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill		0	0
FCC licenses and other		0	0
Definite-lived intangible assets, net		0	0
Other assets		1,127	1,119
Total assets		46,212	48,732
Current liabilities
Accounts payable		0	0
Accrued expenses and other current liabilities		531	625
Current portion of long-term debt, financing and capital lease obligations		3,065	500
Total Current Liabilities		3,596	1,125
Long-term debt, financing and capital lease obligations		11,495	14,574
Deferred tax liabilities		0	0
Note due to consolidated affiliate		10,377	10,361
Other liabilities		961	960
Due to consolidated affiliate		0	0
Total liabilities		26,429	27,020
Total Stockholders' Equity		19,783	21,712
Total Liabilities and Stockholders' equity		46,212	48,732
Successor [Member] | Non-Guarantor Subsidiaries [Member]
Current assets
Short-term investments			20
Accounts and notes receivable, net		1,099	2,160
Device and accessory inventory		1,173	1,359
Current deferred tax asset			62
Prepaid expenses and other current assets		1,908	1,877
Total Current Assets		4,667	5,996
Investment in subsidiaries		0	0
Property, plant and equipment, net		20,297	19,721
Due from consolidated affiliate		0	0
Note receivable from consolidated affiliate		0	0
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill		6,575	6,575
FCC licenses and other		40,073	39,987
Definite-lived intangible assets, net		4,469	5,893
Other assets		620	788
Total assets		76,701	78,960
Current liabilities
Accounts payable		2,899	4,347
Accrued expenses and other current liabilities		3,820	4,625
Current portion of long-term debt, financing and capital lease obligations		1,625	800
Total Current Liabilities		8,344	9,772
Long-term debt, financing and capital lease obligations		8,415	8,426
Deferred tax liabilities		13,959	13,898
Note due to consolidated affiliate		245	458
Other liabilities		3,041	2,991
Due to consolidated affiliate		19,568	21,002
Total liabilities		53,572	56,547
Total Stockholders' Equity		23,129	22,413
Total Liabilities and Stockholders' equity		76,701	78,960
Successor [Member] | Consolidation, Eliminations [Member]
Current assets
Short-term investments			0
Accounts and notes receivable, net		(114)	(111)
Device and accessory inventory		0	0
Current deferred tax asset			0
Prepaid expenses and other current assets		0	0
Total Current Assets		(114)	(111)
Investment in subsidiaries		(42,912)	(44,125)
Property, plant and equipment, net		0	0
Due from consolidated affiliate		(19,568)	(21,002)
Note receivable from consolidated affiliate		(10,622)	(10,819)
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill		0	0
FCC licenses and other		0	0
Definite-lived intangible assets, net		0	0
Other assets		(1,019)	(1,019)
Total assets		(74,235)	(77,076)
Current liabilities
Accounts payable		0	0
Accrued expenses and other current liabilities		(114)	(111)
Current portion of long-term debt, financing and capital lease obligations		0	0
Total Current Liabilities		(114)	(111)
Long-term debt, financing and capital lease obligations		(1,019)	(1,019)
Deferred tax liabilities		0	0
Note due to consolidated affiliate		(10,622)	(10,819)
Other liabilities		0	0
Due to consolidated affiliate		(19,568)	(21,002)
Total liabilities		(31,323)	(32,951)
Total Stockholders' Equity		(42,912)	(44,125)
Total Liabilities and Stockholders' equity		$ (74,235)	$ (77,076)

[1] Includes liabilities in the amounts of $66 million and $90 million as of March 31, 2016 and 2015, respectively, for checks issued in excess of associated bank balances but not yet presented for collection.

[2] (1)For the Successor period beginning October 5, 2012 and ending December 31, 2012, there were approximately 3 million shares of Class B common stock of Starburst II, Inc. issued and outstanding with an immaterial value. These shares were exchanged in connection with the issuance of common stock to SoftBank upon completion of the Merger.