FINANCIAL INSTRUMENTS AND FAIR VALUE MEASUREMENT (Details) (USD $)	12 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2012
Limited Liability Partnerships
Number of limited partnerships that entity sold shares of the partnership		3
Investments in limited partnerships, at carried cost		$ 9,400,000
Realized gain on sale of investment securities		8,800,000
Quoted Prices in Active Markets for Identical Assets (Level 1)
Non-qualified Supplemental Savings Plan
Assets held in Non-qualified Supplement Savings Plan, at Fair Value	14,300,000	10,500,000
Equity securities
Available-for-sale securities
Cost	64,462,000	68,434,000
Gross unrealized gains	157,838,000	237,214,000
Estimated fair value	222,300,000	305,648,000
Equity available-for-sale securities sold, fair value	49,200,000	214,100,000	0
Total gross realized gain on such sales of available-for-sale securities	$ 45,200,000	$ 153,400,000