GOODWILL AND RADIO BROADCASTING LICENSES: (Details) (Income Approach Valuation Technique [Member], USD $) In Millions, unless otherwise specified	Sep. 30, 2014		Sep. 30, 2013		Jun. 30, 2013	Mar. 31, 2013
Schedule Of Goodwill, Radio Broadcasting Licenses And Other Intangible Assets [Line Items]
Pre-tax impairment charge (in millions)	$ 0	[1]	$ 3.7	[1]	$ 9.8	$ 1.4
Discount Rate	9.50%	[1]	10.50%	[1]
Minimum [Member]
Schedule Of Goodwill, Radio Broadcasting Licenses And Other Intangible Assets [Line Items]
Year 1 Market Revenue Growth Rate Range	0.40%	[1]	(0.50%)	[1]
Long-term Market Revenue Growth Rate Range (Years 6 - 10)	1.50%	[1]	1.00%	[1]
Mature Market Share Range	6.40%	[1]	6.70%	[1]
Operating Profit Margin Range	31.10%	[1]	30.30%	[1]
Maximum [Member]
Schedule Of Goodwill, Radio Broadcasting Licenses And Other Intangible Assets [Line Items]
Year 1 Market Revenue Growth Rate Range	1.00%	[1]	2.00%	[1]
Long-term Market Revenue Growth Rate Range (Years 6 - 10)	2.00%	[1]	2.00%	[1]
Mature Market Share Range	26.90%	[1]	27.40%	[1]
Operating Profit Margin Range	47.80%	[1]	40.10%	[1]

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