Statements of Changes in Members’ Equity (Unaudited) (iShares S&P Commodity-Indexed Investing Pool LLC [Member], USD $)	General [Member] iShares S&P Commodity-Indexed Investing Pool LLC [Member] USD ($)	Limited [Member] iShares S&P Commodity-Indexed Investing Pool LLC [Member] USD ($)	iShares S&P Commodity-Indexed Investing Pool LLC [Member] USD ($)
Members’ Equity at Dec. 31, 2011			$ 1,313,308,657
Net investment loss			(6,749,760)
Net realized gain (loss) on short-term investments			(1,604)
Net realized gain (loss) on futures contracts			(9,755,259)
Net change in unrealized appreciation/ depreciation on futures contracts			48,687,049
Members’ Equity at Sep. 30, 2012
Members’ Equity at Dec. 31, 2011	16,718	1,313,291,939	1,313,308,657
Contributions	0	60,395,586	60,395,586
Redemptions	0	(192,357,388)	(192,357,388)
Net investment loss	(114)	(8,768,838)	(8,768,952)
Net realized gain (loss) on short-term investments	0	(1,661)	(1,661)
Net realized gain (loss) on futures contracts	(191)	(14,329,369)	(14,329,560)
Net change in unrealized appreciation/ depreciation on futures contracts	206	9,358,463	9,358,669
Members’ Equity at Dec. 31, 2012	16,619	1,167,588,732	1,167,605,351
Contributions	0	263,677,995	263,677,995
Redemptions	0	(133,315,923)	(133,315,923)
Net investment loss	(87)	(5,895,483)	(5,895,570)
Net realized gain (loss) on short-term investments	0	5,912	5,912
Net realized gain (loss) on futures contracts	(113)	(7,724,677)	(7,724,790)
Net change in unrealized appreciation/ depreciation on futures contracts	(37)	(10,361,745)	(10,361,782)
Members’ Equity at Sep. 30, 2013	16,382	1,273,974,811	1,273,991,193
Members’ Equity at Jun. 30, 2013
Net investment loss			(2,139,974)
Net realized gain (loss) on short-term investments			1,086
Net realized gain (loss) on futures contracts			(944,977)
Net change in unrealized appreciation/ depreciation on futures contracts			45,996,006
Members’ Equity at Sep. 30, 2013			$ 1,273,991,193