Intangible Assets (Indefinite-Lived Intangible Assets) (Details) $ in Millions	9 Months Ended
	Dec. 31, 2015 USD ($)
Indefinite-lived Intangible Assets [Line Items]
Indefinite-lived Intangible Assets, Period Start	$ 39,987
Indefinite-lived Intangible Assets, Period End	40,052
Goodwill, beginning balance	6,575
Goodwill, Period Increase (Decrease)	0
Goodwill, ending balance	6,575
Total indefinite-lived intangible assets including FCC licenses, Trademarks, Goodwill, beginning balance	46,562
Indefinite lived intangible assets period increase decrease	65
Total indefinite-lived intangible assets including FCC licenses, Trademarks, Goodwill, ending balance	46,627
FCC Licenses [Member]
Indefinite-lived Intangible Assets [Line Items]
Indefinite-lived Intangible Assets, Period Start	35,952
Indefinite-lived Intangible Assets, Period Increase (Decrease)	65
Indefinite-lived Intangible Assets, Period End	36,017
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