GOODWILL AND RADIO BROADCASTING LICENSES: (Details) (USD $) In Millions, unless otherwise specified	Jun. 30, 2013		Mar. 31, 2013		Oct. 01, 2012	Jun. 30, 2012
Pre-tax impairment charge (in millions)	$ 9.8	[1]	$ 1.4	[1]	$ 0	$ 0.3	[1]
Discount Rate	10.50%	[1]	10.00%	[1]	10.00%	10.00%	[1]
Year 1 Market Revenue Growth Rate Range	2.00%	[1]	1.00%	[1]
Long-term Market Revenue Growth Rate Range (Years 6 - 10)			1.50%	[1]
Mature Market Share Range			8.60%	[1]
Operating Profit Margin Range			31.40%	[1]
Minimum [Member]
Year 1 Market Revenue Growth Rate Range					1.00%	1.00%	[1]
Long-term Market Revenue Growth Rate Range (Years 6 - 10)	1.50%	[1]			1.00%	1.00%	[1]
Mature Market Share Range	8.60%	[1]			0.70%	5.80%	[1]
Operating Profit Margin Range	32.60%	[1]			19.60%	29.10%	[1]
Maximum [Member]
Year 1 Market Revenue Growth Rate Range					2.00%	3.00%	[1]
Long-term Market Revenue Growth Rate Range (Years 6 - 10)	2.00%	[1]			2.00%	2.00%	[1]
Mature Market Share Range	15.10%	[1]			27.40%	15.60%	[1]
Operating Profit Margin Range	34.40%	[1]			47.70%	48.00%	[1]

[1] Reflects only key assumptions used in the interim testing for certain units of accounting.