Intangible Assets (Tables)

12 Months Ended

Mar. 31, 2015

Goodwill and Intangible Assets Disclosure [Abstract]

Indefinite-Lived Intangible Assets

The following provides the activity of Indefinite-lived intangible assets within the consolidated balance sheets:

	March 31, 2014		Net Additions					March 31, 2015
	(in millions)
FCC licenses	$	36,043	$	(91	)			$	35,952
Trademarks	5,935		(1,900		)	(1	)	4,035
Goodwill	6,383		192			(2	)	6,575
	$	48,361	$	(1,799	)			$	46,562

	December 31, 2013		Net Additions					March 31, 2014
	(in millions)
FCC licenses	$	35,889	$	154				$	36,043
Trademarks	5,935		—					5,935
Goodwill	6,434		(51		)	(3	)	6,383
	$	48,258	$	103				$	48,361

 _________________

(1) Net reduction to trademarks for the year ended March 31, 2015 of approximately $1.9 billion was related to the impairment of the Sprint trade name. See discussion below.

(2) Net additions to goodwill for the Successor year ended March 31, 2015 of approximately $192 million were the result of purchase price allocation adjustments, which consisted of a $232 million increase recorded during the three-month period ended March 31, 2015 to correct the amount of net deferred tax liabilities recognized in connection with the SoftBank Merger and Clearwire Acquisition and a net $40 million decrease recorded during the three-months ended June 30, 2014, which is also associated with the SoftBank Merger and Clearwire Acquisition.

(3) Net reduction to goodwill for the Successor three-month transition period ended March 31, 2014 of $51 million was the result of purchase price allocation adjustments associated with the SoftBank Merger.

Intangible Assets Subject to Amortization

		March 31, 2015							March 31, 2014
	Useful Lives	Gross Carrying Value		Accumulated Amortization			Net Carrying Value		Gross Carrying Value		Accumulated Amortization			Net Carrying Value
		(in millions)
Customer relationships	4 to 8 years	$	6,923	$	(2,791	)	$	4,132	$	6,923	$	(1,289	)	$	5,634
Other intangible assets:
Favorable spectrum leases	23 years	884		(71		)	813		884		(30		)	854
Favorable tower leases	3 to 7 years	589		(189		)	400		589		(80		)	509
Trademarks	34 years	520		(27		)	493		520		(12		)	508
Other	4 to 10 years	72		(17		)	55		60		(7		)	53
Total other intangible assets		2,065		(304		)	1,761		2,053		(129		)	1,924
Total definite-lived intangible assets		$	8,988	$	(3,095	)	$	5,893	$	8,976	$	(1,418	)	$	7,558

Intangible Assets Subject to Amortization, Future Amortization Expense

	Fiscal Year 2015		Fiscal Year 2016		Fiscal Year 2017		Fiscal Year 2018		Fiscal Year 2019
	(in millions)
Estimated amortization expense	$	1,427	$	1,162	$	882	$	665	$	461