CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) shares in Millions, $ in Millions		Total	Common Stock [Member]	Paid-in Capital [Member]	Treasury Shares [Member]	Accumulated Deficit [Member]	Accumulated Other Comprehensive (Loss) Income [Member]	SoftBank [Member]	SoftBank [Member] Common Stock [Member]	SoftBank [Member] Paid-in Capital [Member]	Common Class B [Member] Common Stock [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock, shares, issued | Successor [Member]											3
Balance (in shares) (Predecessor [Member]) at Dec. 31, 2012			3,010		0
Balance (in shares) (Successor [Member]) at Dec. 31, 2012	[1]		0		0
Balance (Predecessor [Member]) at Dec. 31, 2012		$ 7,087	$ 6,019	$ 47,016	$ 0	$ (44,815)	$ (1,133)
Balance (Successor [Member]) at Dec. 31, 2012	[1]	3,110	$ 0	3,137	$ 0	(27)	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income | Predecessor [Member]		(1,158)				(1,158)
Other comprehensive (loss) income | Predecessor [Member]		23					23
Issuance of common stock, net (in shares) | Predecessor [Member]			16
Issuance of common stock, net | Predecessor [Member]		60	$ 33	27
Share-based compensation expense | Predecessor [Member]		18		18
Conversion of convertible debt (in shares) | Predecessor [Member]			590
Conversion of convertible debt | Predecessor [Member]			$ 1,181
Adjustments to paid in capital, conversation of convertible debt | Predecessor [Member]				1,919
Beneficial conversion feature on convertible bond | Predecessor [Member]		3,100
Balance (in shares) (Predecessor [Member]) at Jul. 10, 2013			3,616		0
Balance (Predecessor [Member]) at Jul. 10, 2013		9,130	$ 7,233	48,980	$ 0	(45,973)	(1,110)
Balance (in shares) (Predecessor [Member]) at Dec. 31, 2012			3,010		0
Balance (in shares) (Successor [Member]) at Dec. 31, 2012	[1]		0		0
Balance (Predecessor [Member]) at Dec. 31, 2012		7,087	$ 6,019	47,016	$ 0	(44,815)	(1,133)
Balance (Successor [Member]) at Dec. 31, 2012	[1]	3,110	$ 0	3,137	$ 0	(27)	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income | Successor [Member]		(1,860)				(1,860)
Other comprehensive (loss) income | Successor [Member]		102					102
Issuance of common stock, net (in shares) | Successor [Member]			7
Issuance of common stock, net | Successor [Member]		27		27
Share-based compensation expense | Successor [Member]		45		45
Expenses incurred by SoftBank for the benefit of Sprint | Successor [Member]		97		97
Issuance of common stock to stockholders upon acquisition (in shares) | Successor [Member]			851						3,076
Issuance of common stock to stockholders upon acquisition | Successor [Member]		5,344	$ 8	5,336				$ 18,401	$ 31	$ 18,370
Conversion of Sprint vested stock-based awards upon acquisition | Successor [Member]		193		193
Issuance of warrant to SoftBank prior to acquisition | Successor [Member]		139		139
Return of capital to SoftBank prior to acquisition | Successor [Member]		(14)		(14)
Balance (in shares) (Successor [Member]) at Dec. 31, 2013			3,934		0
Balance (Successor [Member]) at Dec. 31, 2013		25,584	$ 39	27,330	$ 0	(1,887)	102
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income | Successor [Member]		(151)				(151)
Other comprehensive (loss) income | Successor [Member]		(145)					(145)
Issuance of common stock, net (in shares) | Successor [Member]			7
Issuance of common stock, net | Successor [Member]		0
Share-based compensation expense | Successor [Member]		24		24
Balance (in shares) (Successor [Member]) at Mar. 31, 2014			3,941		0
Balance (Successor [Member]) at Mar. 31, 2014		25,312	$ 39	27,354	$ 0	(2,038)	(43)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income | Successor [Member]		(3,345)				(3,345)
Other comprehensive (loss) income | Successor [Member]		(365)					(365)
Issuance of common stock, net (in shares) | Successor [Member]			26
Issuance of common stock, net | Successor [Member]		35	$ 1	41
Issuance (repurchase) of common stock, net (in shares) | Successor [Member]					1
Issuance (repurchase) of common stock, net | Successor [Member]					$ (7)
Share-based compensation expense | Successor [Member]		71		71
Capital contribution by SoftBank | Successor [Member]				2
Balance (in shares) (Successor [Member]) at Mar. 31, 2015			3,967		1
Balance (Successor [Member]) at Mar. 31, 2015		21,710	$ 40	27,468	$ (7)	(5,383)	(408)
Balance at Mar. 31, 2015		$ 21,710
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock, shares, issued | Successor [Member]		3,967
Net (loss) income | Successor [Member]		$ (1,995)				(1,995)
Other comprehensive (loss) income | Successor [Member]		(31)					(31)
Issuance of common stock, net (in shares) | Successor [Member]			7
Issuance of common stock, net | Successor [Member]		10		6
Issuance (repurchase) of common stock, net | Successor [Member]					$ 4
Share-based compensation expense | Successor [Member]		71		71
Capital contribution by SoftBank | Successor [Member]				14
Other, net | Successor [Member]				4
Balance (in shares) (Successor [Member]) at Mar. 31, 2016			3,974		1
Balance (Successor [Member]) at Mar. 31, 2016		19,783	$ 40	$ 27,563	$ (3)	$ (7,378)	$ (439)
Balance at Mar. 31, 2016		$ 19,783
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock, shares, issued | Successor [Member]		3,975

[1] (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.