Note 2 - Summary of Significant Accounting Policies (Details) (USD $)	Sep. 30, 2013	Dec. 31, 2012
iShares S&P Commodity-Indexed Trust [Member]
Note 2 - Summary of Significant Accounting Policies (Details) [Line Items]
Equity Method Investment, Ownership Percentage	99.99%
Deposit Initial Margin Percentage	100.00%
iShares S&P Commodity-Indexed Investing Pool LLC [Member]
Note 2 - Summary of Significant Accounting Policies (Details) [Line Items]
Deposit Initial Margin Percentage	100.00%
Margin Deposit Assets (in Dollars)	$ 19,094,117	$ 53,468,750
Deposits with Clearing Organizations and Others, Securities (in Dollars)	$ 47,504,000	$ 1,111,734,878

Percentage of the value of each Index Future position at which, prior to April 8, 2013, the Investing Pool was required to deposit margin at the time the position was established.

No definition available.

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- Definition

The amount of securities on deposit with clearing organizations and other entities which provide services necessary to operations of the Company. This item would include, for instance, securities advanced as refundable collateral for securities borrowed.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.8,17)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571

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- Definition

The amount of cash or securities placed with a broker or counterparty as security for a trading or derivatives securities position which was partially obtained with funds provided by the broker dealer.

+ References

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