Organization And Business (Additional Information) (Details)
Dec. 31, 2013
United States Commodity Index Fund [Member]
May 01, 2012
United States Commodity Index Fund [Member]
Jul. 01, 2011
United States Commodity Index Fund [Member]
Aug. 10, 2010
United States Commodity Index Fund [Member]
Aug. 10, 2010
United States Commodity Index Fund [Member]
May 01, 2012
United States Commodity Index Fund [Member]
Creation Baskets [Member]
May 01, 2012
United States Commodity Index Fund [Member]
Marketing Agent [Member]
Dec. 31, 2013
United States Copper Index Fund [Member]
May 01, 2012
United States Copper Index Fund [Member]
Nov. 15, 2011
United States Copper Index Fund [Member]
Nov. 15, 2011
United States Copper Index Fund [Member]
May 01, 2012
United States Copper Index Fund [Member]
Creation Baskets [Member]
May 01, 2012
United States Copper Index Fund [Member]
Marketing Agent [Member]
Dec. 31, 2013
United States Agriculture Index Fund [Member]
May 01, 2012
United States Agriculture Index Fund [Member]
Apr. 13, 2012
United States Agriculture Index Fund [Member]
Apr. 13, 2012
United States Agriculture Index Fund [Member]
May 01, 2012
United States Agriculture Index Fund [Member]
Creation Baskets [Member]
May 01, 2012
United States Agriculture Index Fund [Member]
Marketing Agent [Member]
Dec. 31, 2013
United States Metals Index Fund [Member]
Jun. 19, 2012
United States Metals Index Fund [Member]
Jun. 09, 2012
United States Metals Index Fund [Member]
May 01, 2012
United States Metals Index Fund [Member]
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]                                              
Number of Units per basket   50,000       50,000 100,000   50,000     50,000 100,000   50,000     50,000 100,000        
Fee paid by Authorized Purchasers for each order placed to create one or more Creation Baskets or to redeem one or more baskets 350   1,000 1,000 1,000     350 1,000 1,000 1,000     350 1,000 1,000 1,000     350 350 350 1,000