Guarantor Financial Information CONDENSED CONSOLIDATING STATEMENT OF CASH FLOWS (Details) (USD $) In Millions, unless otherwise specified	6 Months Ended										3 Months Ended
	Sep. 30, 2014 Successor [Member]	Sep. 30, 2013 Successor [Member]	Sep. 30, 2014 Successor [Member] Parent Company [Member]	Sep. 30, 2013 Successor [Member] Parent Company [Member]	Sep. 30, 2014 Successor [Member] Guarantor Subsidiaries [Member]	Sep. 30, 2013 Successor [Member] Guarantor Subsidiaries [Member]	Sep. 30, 2014 Successor [Member] Non-Guarantor Subsidiaries [Member]	Sep. 30, 2013 Successor [Member] Non-Guarantor Subsidiaries [Member]	Sep. 30, 2014 Successor [Member] Consolidation, Eliminations [Member]	Sep. 30, 2013 Successor [Member] Consolidation, Eliminations [Member]	Jul. 10, 2013 Predecessor [Member]	Jul. 10, 2013 Predecessor [Member] Guarantor Subsidiaries [Member]	Jul. 10, 2013 Predecessor [Member] Non-Guarantor Subsidiaries [Member]	Jul. 10, 2013 Predecessor [Member] Consolidation, Eliminations [Member]
Cash flows from operating activities
Net Cash Provided by (Used in) Operating Activities	$ 1,707	$ 702	$ 0	$ 11	$ (679)	$ 150	$ 2,586	$ 891	$ (200)	$ (350)	$ 1,731	$ (349)	$ 2,080	$ 0
Cash flows from investing activities
Capital expenditures	(2,389)	(1,878)	0	0	0	0	(2,389)	(1,878)	0	0	(1,759)	0	(1,759)	0
Payments to Acquire Intangible Assets	(79)	(31)	0	0	0	0	(79)	(31)	0	0	(70)	0	(70)	0
Licensee Reimbursed share of costs	95	0	0		0		95		0		0
Acquisitions, net of cash acquired	0	(14,112)		(16,640)		2,528		0		0	(4,039)	(4,039)	0	0
Payments to Acquire Equity Method Investments	0	0									(228)	0	(228)	0
Proceeds from sales and maturities of short-term investments	1,842	479	0	0	1,842	329	0	150	0	0	1,164	1,164	0	0
Payments to Acquire Short-term Investments	(1,789)	(815)	0	(200)	(1,754)	(615)	(35)	0	0	0	(295)	(295)	0	0
Increase in restricted cash	0	(3,050)		0		(2,655)		(395)		0	0
Increase (decrease) due from consolidated affiliate from investing activities	0	0	0	0	(92)	(2,542)	0	0	92	2,542	0	(136)	0	136
Payments to Acquire Businesses and Interest in Affiliates		0		(1,600)		0		0		1,600
Proceeds from sales of assets and FCC Licenses	101	3	0	0	0	0	101	3	0	0	4	0	4	0
Payments for Advance to Affiliate		0		(6,401)		0		0		6,401
Payments for (Proceeds from) Other Investing Activities	(6)	(3)	0	0	0	0	(6)	(3)	0	0	(4)	0	(4)	0
Net Cash Provided by (Used in) Investing Activities	(2,225)	(19,407)	0	(24,841)	(4)	(2,955)	(2,313)	(2,154)	92	10,543	(5,227)	(3,306)	(2,057)	136
Cash flows from financing activities
Proceeds from debt and financings	0	6,826		6,500		0		326		0	0
Repayments of Long-term Debt, Long-term Capital Lease Obligations, and Capital Securities	(363)	(497)	0	0	0	0	(363)	(497)	0	0	(303)	0	(303)	0
Debt financing costs	0	(107)		(99)		0		(8)		0	(1)	(1)	0	0
Proceeds from Issuance of Common Stock	46	18,552	0	18,540	46	12	0	0	0	0	53	53	0	0
Cash Dividends Paid to Parent Company	0	0	0	0	0	0	(200)	(350)	200	350
Increase (decrease) due from/to consolidated affiliates from financing activities	0	0	0	0	0	0	92	2,542	(92)	(2,542)	0	0	136	(136)
Intercompany note advance from parent		0		0		6,401		0		(6,401)
Proceeds from Contributions from Parent		0		0		1,600		0		(1,600)
Other, net	0	(14)		(14)		0		0		0	0
Net cash provided by (used in) financing activities	(317)	24,760	0	24,927	46	8,013	(471)	2,013	108	(10,193)	(251)	52	(167)	(136)
Cash and Cash Equivalents, Period Increase (Decrease)	(835)	6,055	0	97	(637)	5,208	(198)	750	0	0	(3,747)	(3,603)	(144)	0
Cash and cash equivalents, end of period	$ 4,135	$ 6,058	$ 0	$ 100	$ 3,488	$ 5,208	$ 647	$ 750	$ 0	$ 0	$ 2,528	$ 1,521	$ 1,007	$ 0