Note 9 - Investments in U.S. Treasury Notes and Bills and Marketable Securities (Details) (USD $)	9 Months Ended	21 Months Ended
Jun. 30, 2013	Sep. 30, 2012
Note 9 - Investments in U.S. Treasury Notes and Bills and Marketable Securities (Details) [Line Items]
Available-for-sale Securities, Gross Unrealized Gain	$ 80,999,000	$ 54,653,000
Available-for-sale Securities, Gross Unrealized Loss	2,272,000	2,189,000
US Treasury Bills And Marketable Securities [Member]
Note 9 - Investments in U.S. Treasury Notes and Bills and Marketable Securities (Details) [Line Items]
Available-for-sale Securities, Gross Unrealized Gain (Loss)	$ 78,727,000	$ 52,464,000

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Amount of unrealized gain (loss) on investments in debt and equity securities classified as available-for-sale securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 9

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27357-111563

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- Definition

Amount of unrealized gain before deducting unrealized loss on investments in debt and equity securities classified as available-for-sale securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27161-111563

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Amount of unrealized loss before deducting unrealized gain on investments in available-for-sale securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27161-111563

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