Note 9 - Investments in U.S. Treasury Notes and Bills and Marketable Securities (Details) - Investments in U.S. Treasury Notes and Bills and Marketable Securities (USD $)	9 Months Ended	12 Months Ended
	Jun. 30, 2013	Sep. 30, 2012
Total [Member]
Note 9 - Investments in U.S. Treasury Notes and Bills and Marketable Securities (Details) - Investments in U.S. Treasury Notes and Bills and Marketable Securities [Line Items]
Available for sale investment, aggregate fair value	$ 128,421,000	$ 102,956,000
Available for sale investment, amortized cost basis	49,694,000	50,492,000
Available for sale investment, pretax unrealized gains	78,727,000	52,464,000
US Treasury Securities [Member]
Note 9 - Investments in U.S. Treasury Notes and Bills and Marketable Securities (Details) - Investments in U.S. Treasury Notes and Bills and Marketable Securities [Line Items]
Available for sale investment, aggregate fair value	0	800,000
Available for sale investment, amortized cost basis	0	800,000
Available for sale investment, pretax unrealized gains	0	0
Equity Securities [Member]
Note 9 - Investments in U.S. Treasury Notes and Bills and Marketable Securities (Details) - Investments in U.S. Treasury Notes and Bills and Marketable Securities [Line Items]
Available for sale investment, aggregate fair value	121,104,000	94,061,000
Available for sale investment, amortized cost basis	44,761,000	44,761,000
Available for sale investment, pretax unrealized gains	76,343,000	49,300,000
Debt Securities [Member]
Note 9 - Investments in U.S. Treasury Notes and Bills and Marketable Securities (Details) - Investments in U.S. Treasury Notes and Bills and Marketable Securities [Line Items]
Available for sale investment, aggregate fair value	7,317,000	8,095,000
Available for sale investment, amortized cost basis	4,933,000	4,931,000
Available for sale investment, pretax unrealized gains	$ 2,384,000	$ 3,164,000