Intangible Assets (Indefinite-Lived Intangible Assets) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
	Sep. 30, 2016	Sep. 30, 2016
Indefinite-lived Intangible Assets [Line Items]
Document Period End Date		Sep. 30, 2016
Indefinite-lived Intangible Assets, Period Start		$ 40,073
Indefinite-lived Intangible Assets, Period End	$ 40,541	40,541
Goodwill, beginning balance		6,575
Goodwill, Period Increase (Decrease)		0
Goodwill, ending balance	6,575	6,575
Total indefinite-lived intangible assets including FCC licenses, Trademarks, Goodwill, beginning balance		46,648
Indefinite lived intangible assets period increase decrease		468
Total indefinite-lived intangible assets including FCC licenses, Trademarks, Goodwill, ending balance	47,116	47,116
FCC Licenses [Member]
Indefinite-lived Intangible Assets [Line Items]
Indefinite-lived Intangible Assets, Period Start		36,038
Indefinite-lived Intangible Assets, Period Increase (Decrease)		468
Indefinite-lived Intangible Assets, Period End	36,506	36,506
Indefinite-lived Intangible Assets Acquired	85
Trademarks [Member]
Indefinite-lived Intangible Assets [Line Items]
Indefinite-lived Intangible Assets, Period Start		4,035
Indefinite-lived Intangible Assets, Period Increase (Decrease)		0
Indefinite-lived Intangible Assets, Period End	$ 4,035	$ 4,035