Statements of Financial Condition (Unaudited) (iShares S&P Commodity-Indexed Trust [Member], USD $)	Sep. 30, 2013	Dec. 31, 2012
iShares S&P Commodity-Indexed Trust [Member]
Current Assets
Investment in iShares® S&P GSCI™ Commodity-Indexed Investing Pool LLC	$ 1,273,974,811	$ 1,167,588,732
Total Assets	1,273,974,811	1,167,588,732
Commitments and Contingent Liabilities (Note 7)
Redeemable capital Shares, no par value, unlimited amount authorized (at redemption value) – 39,350,000 issued and outstanding at September 30, 2013 and 35,550,000 issued and outstanding at December 31, 2012	1,273,974,811	1,167,588,732
Total Shareholders’ Capital	1,273,974,811	1,167,588,732
Total Liabilities and Shareholders’ Capital	$ 1,273,974,811	$ 1,167,588,732

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