Document_and_Entity_Informatio
| Document and Entity Information | 9 Months Ended | |
| Sep. 30, 2013 | Nov. 04, 2013 | |
| Document Information [Line Items] | ' | ' |
| Document Type | '10-Q | ' |
| Amendment Flag | 'false | ' |
| Document Period End Date | 30-Sep-13 | ' |
| Document Fiscal Year Focus | '2013 | ' |
| Document Fiscal Period Focus | 'Q3 | ' |
| Trading Symbol | 'CTF | ' |
| Entity Registrant Name | 'NUVEEN LONG/SHORT COMMODITY TOTAL RETURN FUND | ' |
| Entity Central Index Key | '0001522699 | ' |
| Current Fiscal Year End Date | '--12-31 | ' |
| Entity Filer Category | 'Non-accelerated Filer | ' |
| Entity Common Stock, Shares Outstanding | ' | 18,300,840 |
Statements_of_Financial_Condit
| Statements of Financial Condition (USD $) | Sep. 30, 2013 | Dec. 31, 2012 | |
| ASSETS | ' | ' | |
| Short-term investments, at value (cost $332,129,934 and $372,233,128, respectively) | $332,244,193 | $372,303,955 | |
| Deposits with brokers | 60,658,316 | 63,184,990 | |
| Unrealized appreciation on futures contracts | 4,806,535 | 1,499,470 | |
| Total assets | 397,709,044 | 436,988,415 | |
| LIABILITIES | ' | ' | |
| Cash overdraft | ' | 928,991 | |
| Options written, at value (premiums received $5,396,164 and $4,747,719, respectively) | 5,486,327 | 3,465,424 | |
| Unrealized depreciation on futures contracts | 5,611,896 | 4,755,125 | |
| Payables for: | ' | ' | |
| Distributions | 2,898,243 | ' | |
| Shares redeemed | 262,788 | ' | |
| Accrued expenses: | ' | ' | |
| Management fees | 400,999 | 460,442 | |
| Independent Committee fees | 28,982 | 25,800 | |
| Other | 449,223 | 241,070 | |
| Total liabilities | 15,138,458 | 9,876,852 | |
| SHAREHOLDERS' CAPITAL | ' | ' | |
| Paid-in capital, unlimited number of shares authorized, 18,683,340 shares issued and outstanding at September 30, 2013 and 18,800,840 shares issued and outstanding at December 31, 2012 | 445,825,423 | 447,930,055 | |
| Accumulated undistributed earnings (deficit) | -63,254,837 | -20,818,492 | |
| Total shareholders' capital (Net assets) | 382,570,586 | 427,111,563 | [1] |
| Total liabilities and shareholders' capital | 397,709,044 | 436,988,415 | |
| Net assets | $382,570,586 | $427,111,563 | |
| Shares outstanding | 18,683,340 | 18,800,840 | |
| Net asset value per share outstanding (net assets divided by shares outstanding) | $20.48 | $22.72 | |
| Market value per share outstanding | $17.23 | $21.22 | |
| [1] | The Fund was organized as a statutory trust under Delaware law on May 25, 2011, and commenced operations on October 25, 2012. | ||
Statements_of_Financial_Condit1
| Statements of Financial Condition (Parenthetical) (USD $) | Sep. 30, 2013 | Dec. 31, 2012 |
| Short-term investments, at cost | $332,129,934 | $372,233,128 |
| Options written, premiums received | $5,396,164 | $4,747,719 |
| Common Stock, Shares authorized | 'Unlimited | 'Unlimited |
| Common Stock, Shares issued | 18,683,340 | 18,800,840 |
| Common Stock, Shares outstanding | 18,683,340 | 18,800,840 |
Schedule_of_Investments
| Schedule of Investments (USD $) | Sep. 30, 2013 | |
| Financial Instruments Owned Us Government and Agency Obligations, Principal Amount | $329,250,000 | |
| Financial Instruments, Owned, US Government and Agency Obligations, at Fair Value | 329,171,513 | |
| Repurchase Agreements, at Fair Value | 3,072,680 | |
| Short-term investments, at Fair Value | 332,244,193 | |
| Repurchase Agreements | ' | |
| Repurchase Agreements, Principal amount | 3,073,000 | |
| Repurchase Agreements, Coupon | 0.00% | |
| Repurchase Agreements, Maturity | 1-Oct-13 | |
| Repurchase Agreements, Ratings | 'N/A | |
| Repurchase Agreements, at Fair Value | 3,072,680 | |
| 12/12/13 | U.S. Treasury Bills | ' | |
| Financial Instruments Owned Us Government and Agency Obligations, Principal Amount | 35,500,000 | |
| Financial Instruments Owned Us Government and Agency Obligations, Interest Rate | 0.00% | |
| Financial Instruments Owned Us Government and Agency Obligations, Maturity Date | 12-Dec-13 | |
| Financial Instruments Owned Us Government and Agency Obligations, Credit Ratings | 'Aaa | [1] |
| Financial Instruments, Owned, US Government and Agency Obligations, at Fair Value | 35,499,113 | |
| 1/09/14 | U.S. Treasury Bills | ' | |
| Financial Instruments Owned Us Government and Agency Obligations, Principal Amount | 44,500,000 | |
| Financial Instruments Owned Us Government and Agency Obligations, Interest Rate | 0.00% | |
| Financial Instruments Owned Us Government and Agency Obligations, Maturity Date | 9-Jan-14 | |
| Financial Instruments Owned Us Government and Agency Obligations, Credit Ratings | 'Aaa | [1] |
| Financial Instruments, Owned, US Government and Agency Obligations, at Fair Value | 44,499,065 | |
| 2/06/14 | U.S. Treasury Bills | ' | |
| Financial Instruments Owned Us Government and Agency Obligations, Principal Amount | 35,000,000 | |
| Financial Instruments Owned Us Government and Agency Obligations, Interest Rate | 0.00% | |
| Financial Instruments Owned Us Government and Agency Obligations, Maturity Date | 6-Feb-14 | |
| Financial Instruments Owned Us Government and Agency Obligations, Credit Ratings | 'Aaa | [1] |
| Financial Instruments, Owned, US Government and Agency Obligations, at Fair Value | 34,998,145 | |
| 3/06/14 | U.S. Treasury Bills | ' | |
| Financial Instruments Owned Us Government and Agency Obligations, Principal Amount | 39,250,000 | |
| Financial Instruments Owned Us Government and Agency Obligations, Interest Rate | 0.00% | |
| Financial Instruments Owned Us Government and Agency Obligations, Maturity Date | 6-Mar-14 | |
| Financial Instruments Owned Us Government and Agency Obligations, Credit Ratings | 'Aaa | [1] |
| Financial Instruments, Owned, US Government and Agency Obligations, at Fair Value | 39,247,449 | |
| 4/03/14 | U.S. Treasury Bills | ' | |
| Financial Instruments Owned Us Government and Agency Obligations, Principal Amount | 35,000,000 | |
| Financial Instruments Owned Us Government and Agency Obligations, Interest Rate | 0.00% | |
| Financial Instruments Owned Us Government and Agency Obligations, Maturity Date | 3-Apr-14 | |
| Financial Instruments Owned Us Government and Agency Obligations, Credit Ratings | 'Aaa | [1] |
| Financial Instruments, Owned, US Government and Agency Obligations, at Fair Value | 34,994,190 | |
| 5/01/14 | U.S. Treasury Bills | ' | |
| Financial Instruments Owned Us Government and Agency Obligations, Principal Amount | 33,000,000 | |
| Financial Instruments Owned Us Government and Agency Obligations, Interest Rate | 0.00% | |
| Financial Instruments Owned Us Government and Agency Obligations, Maturity Date | 1-May-14 | |
| Financial Instruments Owned Us Government and Agency Obligations, Credit Ratings | 'Aaa | [1] |
| Financial Instruments, Owned, US Government and Agency Obligations, at Fair Value | 32,991,750 | |
| 5/29/14 | U.S. Treasury Bills | ' | |
| Financial Instruments Owned Us Government and Agency Obligations, Principal Amount | 30,000,000 | |
| Financial Instruments Owned Us Government and Agency Obligations, Interest Rate | 0.00% | |
| Financial Instruments Owned Us Government and Agency Obligations, Maturity Date | 29-May-14 | |
| Financial Instruments Owned Us Government and Agency Obligations, Credit Ratings | 'Aaa | [1] |
| Financial Instruments, Owned, US Government and Agency Obligations, at Fair Value | 29,991,000 | |
| 6/26/14 | U.S. Treasury Bills | ' | |
| Financial Instruments Owned Us Government and Agency Obligations, Principal Amount | 33,000,000 | |
| Financial Instruments Owned Us Government and Agency Obligations, Interest Rate | 0.00% | |
| Financial Instruments Owned Us Government and Agency Obligations, Maturity Date | 26-Jun-14 | |
| Financial Instruments Owned Us Government and Agency Obligations, Credit Ratings | 'Aaa | [1] |
| Financial Instruments, Owned, US Government and Agency Obligations, at Fair Value | 32,987,097 | |
| 7/24/14 | U.S. Treasury Bills | ' | |
| Financial Instruments Owned Us Government and Agency Obligations, Principal Amount | 4,000,000 | |
| Financial Instruments Owned Us Government and Agency Obligations, Interest Rate | 0.00% | |
| Financial Instruments Owned Us Government and Agency Obligations, Maturity Date | 24-Jul-14 | |
| Financial Instruments Owned Us Government and Agency Obligations, Credit Ratings | 'Aaa | [1] |
| Financial Instruments, Owned, US Government and Agency Obligations, at Fair Value | 3,997,944 | |
| 9/18/14 | U.S. Treasury Bills | ' | |
| Financial Instruments Owned Us Government and Agency Obligations, Principal Amount | 40,000,000 | |
| Financial Instruments Owned Us Government and Agency Obligations, Interest Rate | 0.00% | |
| Financial Instruments Owned Us Government and Agency Obligations, Maturity Date | 18-Sep-14 | |
| Financial Instruments Owned Us Government and Agency Obligations, Credit Ratings | 'Aaa | [1] |
| Financial Instruments, Owned, US Government and Agency Obligations, at Fair Value | $39,965,760 | |
| [1] | Ratings: Using the highest of Standard & Poor's Group, Moody's Investors Service, Inc. or Fitch, Inc. rating. | |
Schedule_of_Investments_Parent
| Schedule of Investments (Parenthetical) (USD $) | 9 Months Ended |
| Sep. 30, 2013 | |
| Total U.S. Government and Agency Obligations,cost | $329,057,254 |
| Total Repurchase Agreements, cost | 3,072,680 |
| Investment agreement name of party | 'State Street Bank |
| Date of repurchase agreement | 30-Sep-13 |
| Repurchase price of agreement | 3,072,680 |
| Short-term investments, at cost | 332,129,934 |
| US Treasury Notes Securities | ' |
| Securities received as collateral face amount | 3,130,000 |
| Securities received as collateral, interest rate | 0.88% |
| Securities received as collateral, maturity date | 28-Feb-17 |
| Securities received as collateral, value | $3,136,182 |
Schedule_of_Investment_in_Deri
| Schedule of Investment in Derivatives (USD $) | Sep. 30, 2013 | |
| Contract | ||
| Derivative [Line Items] | ' | |
| Number of Contracts | -887 | |
| Futures Options, Value | ($5,486,327) | |
| Call Option | Short | ' | |
| Derivative [Line Items] | ' | |
| Number of Contracts | -268 | |
| Futures Options, Value | -1,241,933 | |
| Call Option | Short | Energy | ' | |
| Derivative [Line Items] | ' | |
| Futures Options, Value | -774,811 | |
| Call Option | Short | Agriculture | ' | |
| Derivative [Line Items] | ' | |
| Futures Options, Value | -371,122 | |
| Call Option | Short | Livestock | ' | |
| Derivative [Line Items] | ' | |
| Futures Options, Value | -96,000 | |
| Call Option | Short | Ice Brent Crude Oil Futures | Energy | ' | |
| Derivative [Line Items] | ' | |
| Contract Expiration | 'November 2013 | |
| Number of Contracts | -52 | |
| Strike Price | 104.5 | |
| Futures Options, Value | -223,080 | |
| Call Option | Short | Nymex Crude Oil Futures | Energy | ' | |
| Derivative [Line Items] | ' | |
| Contract Expiration | 'October 2013 | |
| Number of Contracts | -59 | |
| Strike Price | 94.5 | |
| Futures Options, Value | -472,590 | |
| Call Option | Short | Aggregate Crude Oil | Energy | ' | |
| Derivative [Line Items] | ' | |
| Futures Options, Value | -695,670 | |
| Call Option | Short | Nymex Gasoline Rbob Futures | Energy | ' | |
| Derivative [Line Items] | ' | |
| Contract Expiration | 'October 2013 | |
| Number of Contracts | -33 | |
| Strike Price | 26,600 | |
| Futures Options, Value | -79,141 | |
| Call Option | Short | Cbot Soybean Futures | Agriculture | ' | |
| Derivative [Line Items] | ' | |
| Contract Expiration | 'October 2013 | |
| Number of Contracts | -63 | |
| Strike Price | 1,240 | |
| Futures Options, Value | -175,612 | |
| Call Option | Short | Cbot Soybean Meal Futures | Agriculture | ' | |
| Derivative [Line Items] | ' | |
| Contract Expiration | 'November 2013 | |
| Number of Contracts | -21 | |
| Strike Price | 350 | |
| Futures Options, Value | -119,910 | |
| Call Option | Short | Ice Cotton Futures | Agriculture | ' | |
| Derivative [Line Items] | ' | |
| Contract Expiration | 'November 2013 | |
| Number of Contracts | -16 | |
| Strike Price | 78 | |
| Futures Options, Value | -75,600 | |
| Call Option | Short | Cme Lean Hog Futures | Livestock | ' | |
| Derivative [Line Items] | ' | |
| Contract Expiration | 'October 2013 | |
| Number of Contracts | -24 | |
| Strike Price | 82 | |
| Futures Options, Value | -96,000 | |
| Put Option | Short | ' | |
| Derivative [Line Items] | ' | |
| Number of Contracts | -619 | |
| Futures Options, Value | -4,244,394 | |
| Put Option | Short | Metals | ' | |
| Derivative [Line Items] | ' | |
| Futures Options, Value | -2,052,865 | |
| Put Option | Short | Livestock | ' | |
| Derivative [Line Items] | ' | |
| Futures Options, Value | -29,920 | |
| Put Option | Short | Agriculture | ' | |
| Derivative [Line Items] | ' | |
| Futures Options, Value | -2,161,609 | |
| Put Option | Short | Cbot Corn Futures | Agriculture | ' | |
| Derivative [Line Items] | ' | |
| Contract Expiration | 'November 2013 | |
| Number of Contracts | -182 | |
| Strike Price | 540 | |
| Futures Options, Value | -899,763 | |
| Put Option | Short | Cbot Soybean Futures | Agriculture | ' | |
| Derivative [Line Items] | ' | |
| Contract Expiration | 'October 2013 | |
| Number of Contracts | -63 | |
| Strike Price | 1,240 | |
| Futures Options, Value | -40,950 | |
| Put Option | Short | Cbot Wheat Futures | Agriculture | ' | |
| Derivative [Line Items] | ' | |
| Contract Expiration | 'November 2013 | |
| Number of Contracts | -68 | |
| Strike Price | 780 | |
| Futures Options, Value | -357,000 | |
| Put Option | Short | Cbot Soybean Meal Futures | Agriculture | ' | |
| Derivative [Line Items] | ' | |
| Contract Expiration | 'November 2013 | |
| Number of Contracts | -21 | |
| Strike Price | 350 | |
| Futures Options, Value | -3,675 | |
| Put Option | Short | Cbot Soybean Oil Futures | Agriculture | ' | |
| Derivative [Line Items] | ' | |
| Contract Expiration | 'November 2013 | |
| Number of Contracts | -47 | |
| Strike Price | 510 | |
| Futures Options, Value | -279,321 | |
| Put Option | Short | Ice Sugar Futures | Agriculture | ' | |
| Derivative [Line Items] | ' | |
| Contract Expiration | 'February 2014 | |
| Number of Contracts | -101 | |
| Strike Price | 18.75 | |
| Futures Options, Value | -131,219 | |
| Put Option | Short | Ice Coffee C Futures | Agriculture | ' | |
| Derivative [Line Items] | ' | |
| Contract Expiration | 'November 2013 | |
| Number of Contracts | -29 | |
| Strike Price | 155 | |
| Futures Options, Value | -449,681 | |
| Put Option | Short | Cec Gold Futures | Metals | ' | |
| Derivative [Line Items] | ' | |
| Contract Expiration | 'November 2013 | |
| Number of Contracts | -51 | |
| Strike Price | 1,590 | |
| Futures Options, Value | -1,348,950 | |
| Put Option | Short | Cec Silver Futures | Metals | ' | |
| Derivative [Line Items] | ' | |
| Contract Expiration | 'November 2013 | |
| Number of Contracts | -23 | |
| Strike Price | 2,775 | |
| Futures Options, Value | -703,915 | |
| Put Option | Short | Cme Live Cattle Futures | Livestock | ' | |
| Derivative [Line Items] | ' | |
| Contract Expiration | 'October 2013 | |
| Number of Contracts | -34 | |
| Strike Price | 130 | |
| Futures Options, Value | -29,920 | |
| Futures Contracts | ' | |
| Derivative [Line Items] | ' | |
| Unrealized Appreciation (Depreciation) | -805,361 | |
| Futures Contracts | Energy | ' | |
| Derivative [Line Items] | ' | |
| Unrealized Appreciation (Depreciation) | -2,446,508 | |
| Futures Contracts | Agriculture | ' | |
| Derivative [Line Items] | ' | |
| Unrealized Appreciation (Depreciation) | 2,929,794 | |
| Futures Contracts | Metals | ' | |
| Derivative [Line Items] | ' | |
| Unrealized Appreciation (Depreciation) | -1,262,103 | |
| Futures Contracts | Livestock | ' | |
| Derivative [Line Items] | ' | |
| Unrealized Appreciation (Depreciation) | -26,544 | |
| Futures Contracts | Ice Brent Crude Oil Futures | Energy | ' | |
| Derivative [Line Items] | ' | |
| Contract Position | 'Long | |
| Contract Expiration | 'November 2013 | |
| Number of Contracts | 156 | [1] |
| Notional Amount at Value | 16,905,720 | [2] |
| Unrealized Appreciation (Depreciation) | -252,520 | |
| Futures Contracts | Ice Brent Crude Oil Futures One | Energy | ' | |
| Derivative [Line Items] | ' | |
| Contract Position | 'Long | |
| Contract Expiration | 'December 2013 | |
| Number of Contracts | 191 | [1] |
| Notional Amount at Value | 20,519,130 | [2] |
| Unrealized Appreciation (Depreciation) | -180,930 | |
| Futures Contracts | Nymex Crude Oil Futures | Energy | ' | |
| Derivative [Line Items] | ' | |
| Contract Position | 'Long | |
| Contract Expiration | 'November 2013 | |
| Number of Contracts | 228 | [1] |
| Notional Amount at Value | 23,331,240 | [2] |
| Unrealized Appreciation (Depreciation) | -1,086,460 | |
| Futures Contracts | Nymex Crude Oil Futures One | Energy | ' | |
| Derivative [Line Items] | ' | |
| Contract Position | 'Long | |
| Contract Expiration | 'December 2013 | |
| Number of Contracts | 162 | [1] |
| Notional Amount at Value | 16,507,800 | [2] |
| Unrealized Appreciation (Depreciation) | -293,220 | |
| Futures Contracts | Aggregate Crude Oil | Energy | ' | |
| Derivative [Line Items] | ' | |
| Unrealized Appreciation (Depreciation) | -1,813,130 | |
| Futures Contracts | Ice Gas Oil Futures | Energy | ' | |
| Derivative [Line Items] | ' | |
| Contract Position | 'Long | |
| Contract Expiration | 'December 2013 | |
| Number of Contracts | 345 | [1] |
| Notional Amount at Value | 31,334,625 | [2] |
| Unrealized Appreciation (Depreciation) | -260,820 | |
| Futures Contracts | Nymex Gasoline Rbob Futures | Energy | ' | |
| Derivative [Line Items] | ' | |
| Contract Position | 'Long | |
| Contract Expiration | 'November 2013 | |
| Number of Contracts | 33 | [1] |
| Notional Amount at Value | 3,642,685 | [2] |
| Unrealized Appreciation (Depreciation) | -67,259 | |
| Futures Contracts | Nymex Gasoline Rbob Futures One | Energy | ' | |
| Derivative [Line Items] | ' | |
| Contract Position | 'Long | |
| Contract Expiration | 'December 2013 | |
| Number of Contracts | 190 | [1] |
| Notional Amount at Value | 20,833,386 | [2] |
| Unrealized Appreciation (Depreciation) | -305,299 | |
| Futures Contracts | Aggregate Unleaded Gas | Energy | ' | |
| Derivative [Line Items] | ' | |
| Unrealized Appreciation (Depreciation) | -372,558 | |
| Futures Contracts | Cbot Corn Futures | Agriculture | ' | |
| Derivative [Line Items] | ' | |
| Contract Position | 'Short | |
| Contract Expiration | 'December 2013 | |
| Number of Contracts | -1,212 | [1] |
| Notional Amount at Value | -26,754,900 | [2] |
| Unrealized Appreciation (Depreciation) | 2,133,865 | |
| Futures Contracts | Cbot Soybean Futures | Agriculture | ' | |
| Derivative [Line Items] | ' | |
| Contract Position | 'Long | |
| Contract Expiration | 'November 2013 | |
| Number of Contracts | 137 | [1] |
| Notional Amount at Value | 8,786,838 | [2] |
| Unrealized Appreciation (Depreciation) | 138,807 | |
| Futures Contracts | Cbot Soybean Futures One | Agriculture | ' | |
| Derivative [Line Items] | ' | |
| Contract Position | 'Long | |
| Contract Expiration | 'January 2014 | |
| Number of Contracts | 286 | [1] |
| Notional Amount at Value | 18,375,500 | [2] |
| Unrealized Appreciation (Depreciation) | -488,549 | |
| Futures Contracts | Aggregate Soybean | Agriculture | ' | |
| Derivative [Line Items] | ' | |
| Unrealized Appreciation (Depreciation) | -349,742 | |
| Futures Contracts | Cbot Wheat Futures | Agriculture | ' | |
| Derivative [Line Items] | ' | |
| Contract Position | 'Short | |
| Contract Expiration | 'December 2013 | |
| Number of Contracts | -450 | [1] |
| Notional Amount at Value | -15,266,250 | [2] |
| Unrealized Appreciation (Depreciation) | -674,922 | |
| Futures Contracts | Cbot Soybean Meal Futures | Agriculture | ' | |
| Derivative [Line Items] | ' | |
| Contract Position | 'Long | |
| Contract Expiration | 'December 2013 | |
| Number of Contracts | 141 | [1] |
| Notional Amount at Value | 5,716,140 | [2] |
| Unrealized Appreciation (Depreciation) | 488,169 | |
| Futures Contracts | Cbot Soybean Oil Futures | Agriculture | ' | |
| Derivative [Line Items] | ' | |
| Contract Position | 'Short | |
| Contract Expiration | 'December 2013 | |
| Number of Contracts | -320 | [1] |
| Notional Amount at Value | -7,891,200 | [2] |
| Unrealized Appreciation (Depreciation) | 1,128,552 | |
| Futures Contracts | Ice Cotton Futures | Agriculture | ' | |
| Derivative [Line Items] | ' | |
| Contract Position | 'Long | |
| Contract Expiration | 'December 2013 | |
| Number of Contracts | 107 | [1] |
| Notional Amount at Value | 4,665,735 | [2] |
| Unrealized Appreciation (Depreciation) | 45,924 | |
| Futures Contracts | Ice Sugar Futures | Agriculture | ' | |
| Derivative [Line Items] | ' | |
| Contract Position | 'Short | |
| Contract Expiration | 'March 2014 | |
| Number of Contracts | -652 | [1] |
| Notional Amount at Value | -13,246,554 | [2] |
| Unrealized Appreciation (Depreciation) | -540,790 | |
| Futures Contracts | Ice Coffee C Futures | Agriculture | ' | |
| Derivative [Line Items] | ' | |
| Contract Position | 'Short | |
| Contract Expiration | 'December 2013 | |
| Number of Contracts | -193 | [1] |
| Notional Amount at Value | -8,229,037 | [2] |
| Unrealized Appreciation (Depreciation) | 698,738 | |
| Futures Contracts | Cec Copper Futures | Metals | ' | |
| Derivative [Line Items] | ' | |
| Contract Position | 'Short | |
| Contract Expiration | 'December 2013 | |
| Number of Contracts | -111 | [1] |
| Notional Amount at Value | -9,221,325 | [2] |
| Unrealized Appreciation (Depreciation) | -515,363 | |
| Futures Contracts | Cec Gold Futures | Metals | ' | |
| Derivative [Line Items] | ' | |
| Contract Position | 'Short | |
| Contract Expiration | 'December 2013 | |
| Number of Contracts | -338 | [1] |
| Notional Amount at Value | -44,852,600 | [2] |
| Unrealized Appreciation (Depreciation) | -150,620 | |
| Futures Contracts | Cec Silver Futures | Metals | ' | |
| Derivative [Line Items] | ' | |
| Contract Position | 'Short | |
| Contract Expiration | 'December 2013 | |
| Number of Contracts | -153 | [1] |
| Notional Amount at Value | -16,606,620 | [2] |
| Unrealized Appreciation (Depreciation) | -596,120 | |
| Futures Contracts | Cme Live Cattle Futures | Livestock | ' | |
| Derivative [Line Items] | ' | |
| Contract Position | 'Short | |
| Contract Expiration | 'October 2013 | |
| Number of Contracts | -38 | [1] |
| Notional Amount at Value | -1,943,320 | [2] |
| Unrealized Appreciation (Depreciation) | -48,960 | |
| Futures Contracts | Cme Live Cattle Futures One | Livestock | ' | |
| Derivative [Line Items] | ' | |
| Contract Position | 'Short | |
| Contract Expiration | 'December 2013 | |
| Number of Contracts | -190 | [1] |
| Notional Amount at Value | -10,030,100 | [2] |
| Unrealized Appreciation (Depreciation) | -150,064 | |
| Futures Contracts | Aggregate Live Cattle | Livestock | ' | |
| Derivative [Line Items] | ' | |
| Unrealized Appreciation (Depreciation) | -199,024 | |
| Futures Contracts | Cme Lean Hog Futures | Livestock | ' | |
| Derivative [Line Items] | ' | |
| Contract Position | 'Long | |
| Contract Expiration | 'October 2013 | |
| Number of Contracts | 29 | [1] |
| Notional Amount at Value | 1,066,910 | [2] |
| Unrealized Appreciation (Depreciation) | 78,750 | |
| Futures Contracts | Cme Lean Hog Futures One | Livestock | ' | |
| Derivative [Line Items] | ' | |
| Contract Position | 'Long | |
| Contract Expiration | 'December 2013 | |
| Number of Contracts | 134 | [1] |
| Notional Amount at Value | 4,643,100 | [2] |
| Unrealized Appreciation (Depreciation) | 93,730 | |
| Futures Contracts | Aggregate Lean Hogs | Livestock | ' | |
| Derivative [Line Items] | ' | |
| Unrealized Appreciation (Depreciation) | $172,480 | |
| [1] | The aggregate number of contracts for long and short futures contracts outstanding is 2,139 and (3,657), respectively. | |
| [2] | The aggregate notional amount at value for long and short futures contracts outstanding is $176,328,809 and $(154,041,906), respectively. | |
Schedule_of_Investment_in_Deri1
| Schedule of Investment in Derivatives (Parenthetical) (USD $) | Sep. 30, 2013 |
| Derivative [Line Items] | ' |
| Total Call Options Written outstanding | $5,396,164 |
| Long Futures Contracts | ' |
| Derivative [Line Items] | ' |
| Aggregate number of contracts | 2,139 |
| Aggregate notional amount at value | 176,328,809 |
| Short Futures Contracts | ' |
| Derivative [Line Items] | ' |
| Aggregate number of contracts | 3,657 |
| Aggregate notional amount at value | -154,041,906 |
| Call Option | Short | ' |
| Derivative [Line Items] | ' |
| Total Call Options Written outstanding | 1,573,165 |
| Put Option | Short | ' |
| Derivative [Line Items] | ' |
| Total Call Options Written outstanding | $3,822,999 |
Statements_of_Operations
| Statements of Operations (USD $) | 3 Months Ended | 9 Months Ended | ||||
| Sep. 30, 2013 | Sep. 30, 2012 | Sep. 30, 2013 | Sep. 30, 2012 | |||
| Investment Income: | ' | ' | ' | ' | ||
| Interest | $105,432 | ' | $359,359 | ' | ||
| Total Investment Income | 105,432 | ' | 359,359 | ' | ||
| Expenses: | ' | ' | ' | ' | ||
| Management fees | 1,241,107 | ' | 3,767,102 | ' | ||
| Brokerage commissions | 76,848 | ' | 399,380 | ' | ||
| Custodian fees and expenses | 50,618 | ' | 125,110 | ' | ||
| Organization expenses | ' | 4,000 | [1] | ' | 210,000 | [1] |
| Independent Committee fees and expenses | 28,982 | ' | 87,392 | ' | ||
| Professional fees | 152,269 | ' | 391,573 | ' | ||
| Shareholder reporting expenses | 61,966 | ' | 146,573 | ' | ||
| Licensing fees | 98,103 | ' | 310,402 | ' | ||
| Other expenses | 4,372 | ' | 17,363 | ' | ||
| Total expenses before expense reimbursement | 1,714,265 | 4,000 | [1] | 5,244,895 | 210,000 | [1] |
| Expense reimbursement | ' | -4,000 | [1] | ' | -210,000 | [1] |
| Net expenses | 1,714,265 | ' | 5,244,895 | ' | ||
| Net investment income (loss) | -1,608,833 | ' | -4,885,536 | ' | ||
| Net realized gain (loss) from: | ' | ' | ' | ' | ||
| Short-term investments | 1,729 | ' | 6,485 | ' | ||
| Futures contracts | 3,281,234 | ' | -36,509,336 | ' | ||
| Options written | 8,155,319 | ' | 24,030,840 | ' | ||
| Change in net unrealized appreciation (depreciation) of: | ' | ' | ' | ' | ||
| Short-term investments | 64,740 | ' | 43,432 | ' | ||
| Futures contracts | -14,172,136 | ' | 2,450,294 | ' | [1] | |
| Options written | 855,281 | ' | -1,372,458 | ' | ||
| Net realized gain (loss) and change in net unrealized appreciation (depreciation) | -1,813,833 | ' | -11,350,743 | ' | ||
| Net income (loss) | ($3,422,666) | ' | ($16,236,279) | ' | ||
| Net income (loss) per weighted-average share | ($0.18) | ' | [1],[2] | ($0.86) | ' | [1],[2] |
| Weighted-average shares outstanding | 18,766,120 | 840 | [1] | 18,786,546 | 840 | [1] |
| [1] | The Fund was organized as a statutory trust under Delaware law on May 25, 2011, and commenced operations on October 25, 2012. | |||||
| [2] | The Fund issued 840 shares (initial issuance of shares to the Manager) on August 31, 2011. | |||||
Statements_of_Operations_Paren
| Statements of Operations (Parenthetical) | Aug. 31, 2011 |
| Issuance of shares | 840 |
Statements_of_Changes_in_Share
| Statements of Changes in Shareholder's Capital (USD $) | 3 Months Ended | 9 Months Ended | 12 Months Ended | ||||
| Sep. 30, 2013 | Sep. 30, 2013 | Sep. 30, 2012 | Dec. 31, 2012 | ||||
| Shareholders' capital-beginning of period | ' | $427,111,563 | [1] | $20,055 | [1] | $20,055 | [1] |
| Issuance of shares, net of offering costs | ' | ' | ' | 447,910,000 | [1] | ||
| Repurchase of shares | ' | -2,104,632 | ' | ' | |||
| Net increase (decrease) in shareholders' capital resulting from operations: | ' | ' | ' | ' | |||
| Net investment income (loss) | -1,608,833 | -4,885,536 | ' | -1,275,616 | [1] | ||
| Net realized gain (loss) from: | ' | ' | ' | ' | |||
| Short-term investments | 1,729 | 6,485 | ' | 13 | [1] | ||
| Futures contracts | 3,281,234 | -36,509,336 | ' | -15,702,338 | [1] | ||
| Options written | 8,155,319 | 24,030,840 | ' | 976,112 | [1] | ||
| Change in net unrealized appreciation (depreciation) of: | ' | ' | ' | ' | |||
| Short-term investments | 64,740 | 43,432 | ' | 70,827 | [1] | ||
| Futures contracts | -14,172,136 | 2,450,294 | ' | [1] | -3,255,655 | [1] | |
| Options written | 855,281 | -1,372,458 | ' | 1,282,295 | [1] | ||
| Net income (loss) | -3,422,666 | -16,236,279 | ' | -17,904,362 | [1] | ||
| Distributions to shareholders | ' | -26,200,066 | ' | -2,914,130 | [1] | ||
| Shareholders' capital-end of period | $382,570,586 | $382,570,586 | ' | $427,111,563 | [1] | ||
| Shares-beginning of period | ' | 18,800,840 | [1] | 840 | [1] | 840 | [1] |
| Issuance of shares | ' | ' | ' | 18,800,000 | [1] | ||
| Repurchase of shares | ' | -117,500 | ' | ' | |||
| Shares-end of period | 18,683,340 | 18,683,340 | ' | 18,800,840 | [1] | ||
| [1] | The Fund was organized as a statutory trust under Delaware law on May 25, 2011, and commenced operations on October 25, 2012. | ||||||
Statements_of_Cash_Flows
| Statements of Cash Flows (USD $) | 9 Months Ended | 12 Months Ended | |||
| Sep. 30, 2013 | Sep. 30, 2012 | Dec. 31, 2012 | |||
| Cash flows from operating activities: | ' | ' | ' | ||
| Net income (loss) | ($16,236,279) | ' | ($17,904,362) | [1] | |
| Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities: | ' | ' | ' | ||
| Purchases of short-term investments | -824,830,184 | ' | ' | ||
| Proceeds from sales and maturities of short-term investments | 865,299,063 | ' | ' | ||
| Premiums received for options written | 28,263,262 | ' | ' | ||
| Cash paid for options written | -3,583,977 | ' | ' | ||
| Amortization (Accretion) | -359,200 | ' | ' | ||
| (Increase) Decrease in: | ' | ' | ' | ||
| Deposits with brokers | 2,526,674 | ' | ' | ||
| Receivable from Manager | ' | -210,000 | [1] | ' | |
| Increase (Decrease) in: | ' | ' | ' | ||
| Payable for organization expenses | ' | 210,000 | [1] | ' | |
| Accrued management fees | -59,443 | ' | ' | ||
| Accrued independent committee fees | 3,182 | ' | ' | ||
| Accrued other expenses | 208,153 | ' | ' | ||
| Net realized (gain) loss from: | ' | ' | ' | ||
| Short-term investments | -6,485 | ' | -13 | [1] | |
| Options written | -24,030,840 | ' | -976,112 | [1] | |
| Change in net unrealized (appreciation) depreciation of: | ' | ' | ' | ||
| Short-term investments | -43,432 | ' | -70,827 | [1] | |
| Futures contracts | -2,450,294 | ' | [1] | 3,255,655 | [1] |
| Options written | 1,372,458 | ' | -1,282,295 | [1] | |
| Net cash provided by (used in) operating activities | 26,072,658 | 0 | [1] | ' | |
| Cash flows from financing activities: | ' | ' | ' | ||
| Increase (Decrease) in cash overdraft | -928,991 | ' | ' | ||
| Cash paid for shares repurchased | -1,841,844 | ' | ' | ||
| Cash distributions paid to shareholders | -23,301,823 | ' | ' | ||
| Net cash provided by (used in) financing activities | -26,072,658 | 0 | [1] | ' | |
| Net increase (decrease) in cash | ' | ' | [1] | ' | |
| Cash-beginning of period | ' | 20,055 | [1] | 20,055 | [1] |
| Cash-end of period | ' | $20,055 | [1] | ' | |
| [1] | The Fund was organized as a statutory trust under Delaware law on May 25, 2011, and commenced operations on October 25, 2012. | ||||
Schedule_of_Investments1
| Schedule of Investments | 9 Months Ended | ||||||||||||||||||
| Sep. 30, 2013 | |||||||||||||||||||
| Schedule of Investments | ' | ||||||||||||||||||
| NUVEEN LONG/SHORT COMMODITY TOTAL RETURN FUND | |||||||||||||||||||
| SCHEDULE OF INVESTMENTS (Unaudited) | |||||||||||||||||||
| 30-Sep-13 | |||||||||||||||||||
| Investments | |||||||||||||||||||
| Principal | Description | Coupon | Maturity | Ratings(1) | Value | ||||||||||||||
| Amount (000) | |||||||||||||||||||
| Short-Term Investments | |||||||||||||||||||
| U.S. Government and Agency Obligations | |||||||||||||||||||
| $ 35,500 | U.S. Treasury Bills | 0 | % | 12/12/13 | Aaa | $ | 35,499,113 | ||||||||||||
| 44,500 | U.S. Treasury Bills | 0 | % | 1/9/14 | Aaa | 44,499,065 | |||||||||||||
| 35,000 | U.S. Treasury Bills | 0 | % | 2/6/14 | Aaa | 34,998,145 | |||||||||||||
| 39,250 | U.S. Treasury Bills | 0 | % | 3/6/14 | Aaa | 39,247,449 | |||||||||||||
| 35,000 | U.S. Treasury Bills | 0 | % | 4/3/14 | Aaa | 34,994,190 | |||||||||||||
| 33,000 | U.S. Treasury Bills | 0 | % | 5/1/14 | Aaa | 32,991,750 | |||||||||||||
| 30,000 | U.S. Treasury Bills | 0 | % | 5/29/14 | Aaa | 29,991,000 | |||||||||||||
| 33,000 | U.S. Treasury Bills | 0 | % | 6/26/14 | Aaa | 32,987,097 | |||||||||||||
| 4,000 | U.S. Treasury Bills | 0 | % | 7/24/14 | Aaa | 3,997,944 | |||||||||||||
| 40,000 | U.S. Treasury Bills | 0 | % | 9/18/14 | Aaa | 39,965,760 | |||||||||||||
| $ 329,250 | Total U.S. Government and Agency Obligations (cost $329,057,254) | 329,171,513 | |||||||||||||||||
| Repurchase Agreements | |||||||||||||||||||
| $ 3,073 | Repurchase Agreement with State Street Bank, dated 9/30/13, repurchase price $3,072,680, collateralized by $3,130,000 U.S. Treasury Notes, 0.875%, due 2/28/17, value $3,136,182 | 0 | % | 10/1/13 | N/A | $ | 3,072,680 | ||||||||||||
| Total Repurchase Agreements (cost $3,072,680) | 3,072,680 | ||||||||||||||||||
| Total Short-Term Investments (cost $332,129,934) | $ | 332,244,193 | |||||||||||||||||
| Investments in Derivatives | |||||||||||||||||||
| Futures Contracts outstanding: | |||||||||||||||||||
| Commodity | Contract | Contract | Contract | Number | Notional | Unrealized | |||||||||||||
| Group | Position | Expiration | of | Amount | Appreciation | ||||||||||||||
| Contracts(2) | at Value(3) | (Depreciation) | |||||||||||||||||
| Energy | Crude Oil | ||||||||||||||||||
| ICE Brent Crude Oil Futures Contract | Long | November 2013 | 156 | $ | 16,905,720 | $ | (252,520 | ) | |||||||||||
| ICE Brent Crude Oil Futures Contract | Long | Dec-13 | 191 | 20,519,130 | (180,930 | ) | |||||||||||||
| NYMEX Crude Oil Futures Contract | Long | Nov-13 | 228 | 23,331,240 | (1,086,460 | ) | |||||||||||||
| NYMEX Crude Oil Futures Contract | Long | Dec-13 | 162 | 16,507,800 | (293,220 | ) | |||||||||||||
| Total Crude Oil | (1,813,130 | ) | |||||||||||||||||
| Heating Oil | |||||||||||||||||||
| ICE Gas Oil Futures Contract | Long | Dec-13 | 345 | 31,334,625 | (260,820 | ) | |||||||||||||
| Unleaded Gas | |||||||||||||||||||
| NYMEX Gasoline RBOB Futures Contract | Long | Nov-13 | 33 | 3,642,685 | (67,259 | ) | |||||||||||||
| NYMEX Gasoline RBOB Futures Contract | Long | Dec-13 | 190 | 20,833,386 | (305,299 | ) | |||||||||||||
| Total Unleaded Gas | (372,558 | ) | |||||||||||||||||
| Total Energy | (2,446,508 | ) | |||||||||||||||||
| Agriculture | Corn | ||||||||||||||||||
| CBOT Corn Futures Contract | Short | December 2013 | (1,212 | ) | $ | (26,754,900 | ) | $ | 2,133,865 | ||||||||||
| Soybean | |||||||||||||||||||
| CBOT Soybean Futures Contract | Long | Nov-13 | 137 | 8,786,838 | 138,807 | ||||||||||||||
| CBOT Soybean Futures Contract | Long | Jan-14 | 286 | 18,375,500 | (488,549 | ) | |||||||||||||
| Total Soybean | (349,742 | ) | |||||||||||||||||
| Wheat | |||||||||||||||||||
| CBOT Wheat Futures Contract | Short | Dec-13 | (450 | ) | (15,266,250 | ) | (674,922 | ) | |||||||||||
| Soybean Meal | |||||||||||||||||||
| CBOT Soybean Meal Futures Contract | Long | Dec-13 | 141 | 5,716,140 | 488,169 | ||||||||||||||
| Soybean Oil | |||||||||||||||||||
| CBOT Soybean Oil Futures Contract | Short | Dec-13 | (320 | ) | (7,891,200 | ) | 1,128,552 | ||||||||||||
| Cotton | |||||||||||||||||||
| ICE Cotton Futures Contract | Long | Dec-13 | 107 | 4,665,735 | 45,924 | ||||||||||||||
| Sugar | |||||||||||||||||||
| ICE Sugar Futures Contract | Short | Mar-14 | (652 | ) | (13,246,554 | ) | (540,790 | ) | |||||||||||
| Coffee | |||||||||||||||||||
| ICE Coffee C Futures Contract | Short | Dec-13 | (193 | ) | (8,229,037 | ) | 698,738 | ||||||||||||
| Total Agriculture | 2,929,794 | ||||||||||||||||||
| Metals | Copper | ||||||||||||||||||
| CEC Copper Futures Contract | Short | Dec-13 | (111 | ) | (9,221,325 | ) | (515,363 | ) | |||||||||||
| Gold | |||||||||||||||||||
| CEC Gold Futures Contract | Short | Dec-13 | (338 | ) | (44,852,600 | ) | (150,620 | ) | |||||||||||
| Silver | |||||||||||||||||||
| CEC Silver Futures Contract | Short | Dec-13 | (153 | ) | (16,606,620 | ) | (596,120 | ) | |||||||||||
| Total Metals | (1,262,103 | ) | |||||||||||||||||
| Livestock | Live Cattle | ||||||||||||||||||
| CME Live Cattle Futures Contract | Short | Oct-13 | (38 | ) | (1,943,320 | ) | (48,960 | ) | |||||||||||
| CME Live Cattle Futures Contract | Short | Dec-13 | (190 | ) | (10,030,100 | ) | (150,064 | ) | |||||||||||
| Total Live Cattle | (199,024 | ) | |||||||||||||||||
| Lean Hogs | |||||||||||||||||||
| CME Lean Hogs Futures Contract | Long | Oct-13 | 29 | 1,066,910 | 78,750 | ||||||||||||||
| CME Lean Hogs Futures Contract | Long | Dec-13 | 134 | 4,643,100 | 93,730 | ||||||||||||||
| Total Lean Hogs | 172,480 | ||||||||||||||||||
| Total Livestock | (26,544 | ) | |||||||||||||||||
| Total Futures Contracts outstanding | $ | (805,361 | ) | ||||||||||||||||
| Call Options Written outstanding: | |||||||||||||||||||
| Commodity | Contract | Contract | Number | Strike | Value | ||||||||||||||
| Group | Expiration | of | Price | ||||||||||||||||
| Contracts | |||||||||||||||||||
| Energy | Crude Oil | ||||||||||||||||||
| ICE Brent Crude Oil Futures Options | Nov-13 | (52 | ) | $ | 104.5 | $ | (223,080 | ) | |||||||||||
| NYMEX Crude Oil Futures Options | Oct-13 | (59 | ) | 94.5 | (472,590 | ) | |||||||||||||
| Total Crude Oil | (695,670 | ) | |||||||||||||||||
| Unleaded Gas | |||||||||||||||||||
| NYMEX Gasoline RBOB Futures Options | Oct-13 | (33 | ) | 26,600.00 | (79,141 | ) | |||||||||||||
| Total Energy | (774,811 | ) | |||||||||||||||||
| Agriculture | Soybean | ||||||||||||||||||
| CBOT Soybean Futures Options | Oct-13 | (63 | ) | 1,240.00 | (175,612 | ) | |||||||||||||
| Soybean Meal | |||||||||||||||||||
| CBOT Soybean Meal Futures Options | November 2013 | (21 | ) | 350 | (119,910 | ) | |||||||||||||
| Cotton | |||||||||||||||||||
| ICE Cotton Futures Options | Nov-13 | (16 | ) | 78 | (75,600 | ) | |||||||||||||
| Total Agriculture | (371,122 | ) | |||||||||||||||||
| Livestock | Lean Hogs | ||||||||||||||||||
| CME Lean Hogs Futures Options | Oct-13 | (24 | ) | 82 | (96,000 | ) | |||||||||||||
| Total Livestock | (96,000 | ) | |||||||||||||||||
| Total Call Options Written outstanding | |||||||||||||||||||
| (premiums received $1,573,165) | (268 | ) | $ | (1,241,933 | ) | ||||||||||||||
| Put Options Written outstanding: | |||||||||||||||||||
| Commodity | Contract | Contract | Number | Strike | Value | ||||||||||||||
| Group | Expiration | of | Price | ||||||||||||||||
| Contracts | |||||||||||||||||||
| Agriculture | Corn | ||||||||||||||||||
| CBOT Corn Futures Options | Nov-13 | (182 | ) | $ | 540 | $ | (899,763 | ) | |||||||||||
| Soybean | |||||||||||||||||||
| CBOT Soybean Futures Options | Oct-13 | (63 | ) | 1,240.00 | (40,950 | ) | |||||||||||||
| Wheat | |||||||||||||||||||
| CBOT Wheat Futures Options | Nov-13 | (68 | ) | 780 | (357,000 | ) | |||||||||||||
| Soybean Meal | |||||||||||||||||||
| CBOT Soybean Meal Futures Options | Nov-13 | (21 | ) | 350 | (3,675 | ) | |||||||||||||
| Soybean Oil | |||||||||||||||||||
| CBOT Soybean Oil Futures Options | Nov-13 | (47 | ) | 510 | (279,321 | ) | |||||||||||||
| Sugar | |||||||||||||||||||
| ICE Sugar Futures Options | Feb-14 | (101 | ) | 18.75 | (131,219 | ) | |||||||||||||
| Coffee | |||||||||||||||||||
| ICE Coffee C Futures Options | Nov-13 | (29 | ) | 155 | (449,681 | ) | |||||||||||||
| Total Agriculture | (2,161,609 | ) | |||||||||||||||||
| Metals | Gold | ||||||||||||||||||
| CEC Gold Futures Options | Nov-13 | (51 | ) | 1,590.00 | (1,348,950 | ) | |||||||||||||
| Silver | |||||||||||||||||||
| CEC Silver Futures Options | November 2013 | (23 | ) | 2,775.00 | (703,915 | ) | |||||||||||||
| Total Metals | (2,052,865 | ) | |||||||||||||||||
| Livestock | Live Cattle | ||||||||||||||||||
| CME Live Cattle Futures Options | Oct-13 | (34 | ) | 130 | (29,920 | ) | |||||||||||||
| Total Livestock | (29,920 | ) | |||||||||||||||||
| Total Put Options Written outstanding | |||||||||||||||||||
| (premiums received $3,822,999) | (619 | ) | $ | (4,244,394 | ) | ||||||||||||||
| Total Options Written outstanding | |||||||||||||||||||
| (premiums received $5,396,164) | (887 | ) | $ | (5,486,327 | ) | ||||||||||||||
| -1 | Ratings: Using the highest of Standard & Poor’s Group, Moody’s Investors Service, Inc. or Fitch, Inc. rating. | ||||||||||||||||||
| -2 | The aggregate number of contracts for long and short futures contracts outstanding is 2,139 and (3,657), respectively. | ||||||||||||||||||
| -3 | The aggregate notional amount at value for long and short futures contracts outstanding is $176,328,809 and $(154,041,906), respectively. | ||||||||||||||||||
| N/A | Not applicable. | ||||||||||||||||||
| CBOT | Chicago Board of Trade | ||||||||||||||||||
| CEC | Commodities Exchange Center | ||||||||||||||||||
| CME | Chicago Mercantile Exchange | ||||||||||||||||||
| ICE | Intercontinental Exchange | ||||||||||||||||||
| NYMEX | New York Mercantile Exchange | ||||||||||||||||||
| RBOB | Reformulated Gasoline Blendstock Oxygen Blending | ||||||||||||||||||
Organization
| Organization | 9 Months Ended | |||
| Sep. 30, 2013 | ||||
| Organization | ' | |||
| 1. Organization | ||||
| The Nuveen Long/Short Commodity Total Return Fund (the “Fund”) was organized as a Delaware statutory trust on May 25, 2011, to operate as a commodity pool. Nuveen Commodities Asset Management, LLC, the Fund’s manager (“NCAM” or the “Manager”), a wholly-owned subsidiary of Nuveen Investments, Inc. (“Nuveen Investments”), is a Delaware limited liability company registered as a commodity pool operator with the Commodity Futures Trading Commission (the “CFTC”) and is a member of the National Futures Association (the “NFA”). The Fund commenced operations on October 25, 2012, with its initial public offering of 18,800,000 shares. The Fund operates pursuant to an Amended and Restated Trust Agreement dated September 14, 2012 (the “Trust Agreement”). The Fund’s shares represent units of fractional undivided beneficial interest in, and ownership of, the Fund. The Fund’s shares trade on the NYSE MKT under the ticker symbol “CTF.” The Fund is not a mutual fund, a closed-end fund, or any other type of “investment company” within the meaning of the Investment Company Act of 1940, as amended, and is not subject to regulation thereunder. | ||||
| Prior to its initial public offering, the Fund had no operations other than those related to organizational matters, the initial contribution of $20,055 by the Manager, the recording of the Fund’s organizational expenses of $452,000 and their reimbursement by Nuveen Securities, LLC, (“Nuveen”), a wholly-owned subsidiary of Nuveen Investments. The initial contribution of $20,055 by the Manager was received on August 31, 2011, in exchange for 840 Fund shares. | ||||
| The Manager has selected its affiliate, Gresham Investment Management LLC (“Gresham LLC”), acting through its Near Term Active division (in that capacity, “Gresham” or the “Commodity Sub-advisor”), to manage the Fund’s commodity investment strategy and its options strategy. Gresham LLC is a Delaware limited liability company, the successor to Gresham Investment Management, Inc., formed in July 1992. Gresham LLC is registered with the CFTC as a commodity trading advisor and commodity pool operator, is a member of the NFA and is registered with the Securities and Exchange Commission (the “SEC”) as an investment adviser. | ||||
| The Manager has selected its affiliate, Nuveen Asset Management, LLC (“Nuveen Asset Management” or the “Collateral Sub-advisor”), to manage the Fund’s collateral invested in cash equivalents, U.S. government securities and other short-term, high grade debt securities. Nuveen Asset Management is a Delaware limited liability company and is registered with the SEC as an investment adviser. | ||||
| The Fund’s investment objective is to generate attractive total returns. The Fund is actively managed and seeks to outperform its benchmark, the Morningstar® Long/Short Commodity IndexSM (the “Index”). In pursuing its investment objective, the Fund will invest directly in a diverse portfolio of exchange-traded commodity futures contracts that represent the main commodity sectors and are among the most actively traded futures contracts in the global commodity markets. Generally, individual commodity futures positions may be either long or short (or flat in the case of energy futures contracts) depending upon market conditions. The Fund’s Commodity Sub-advisor uses a rules based approach to determine the commodity futures contracts in which the Fund will invest, their respective weightings, and whether the futures positions in each commodity are held long, short or flat. The Fund’s commodity investments will, at all times, be fully collateralized. The Fund is not leveraged, and the notional amount of its combined long, short and flat futures positions will not exceed 100% of the Fund’s net assets. The Fund will also employ a commodity option writing strategy that seeks to produce option premiums for the purpose of enhancing the Fund’s risk-adjusted total return over time. The Fund’s investment strategy will utilize the Commodity Sub-advisor’s proprietary long/short commodity investment program, which has three principal elements: | ||||
| • | An actively managed long/short portfolio of exchange-traded commodity futures contracts; | |||
| • | A portfolio of exchange-traded commodity option contracts; and | |||
| • | A collateral portfolio of cash equivalents, U.S. government securities and other short-term, high grade debt securities. | |||
Summary_of_Significant_Account
| Summary of Significant Accounting Policies | 9 Months Ended | ||||||||||||||||
| Sep. 30, 2013 | |||||||||||||||||
| Summary of Significant Accounting Policies | ' | ||||||||||||||||
| 2. Summary of Significant Accounting Policies | |||||||||||||||||
| The following is a summary of significant accounting policies followed by the Fund in the preparation of its financial statements in accordance with accounting principles generally accepted in the United States (“U.S. GAAP”). The presentation of “Unrealized appreciation and depreciation on futures contracts” on the Statements of Financial Condition has been reclassified to conform to the September 30, 2013 presentation. | |||||||||||||||||
| The accompanying unaudited financial statements were prepared in accordance with U.S. GAAP for interim financial information and with the instructions for Form 10-Q and the rules and regulations of the SEC. In the opinion of management, all material adjustments, consisting only of normal recurring adjustments, considered necessary for a fair statement of the interim period financial statements have been made. Interim period results are not necessarily indicative of results for a full-year period. These financial statements and the notes thereto should be read in conjunction with the Fund’s financial statements included in the Fund’s Annual Report on Form 10-K for the year ended December 31, 2012. | |||||||||||||||||
| Basis of Accounting | |||||||||||||||||
| The accompanying financial statements have been prepared in conformity with U.S. GAAP. The preparation of financial statements in conformity with U.S. GAAP requires management to make certain estimates and assumptions that affect the reported amounts of assets and liabilities and disclosures of contingent assets and liabilities at the date of the financial statements and the reported amounts of increases and decreases in net assets from operations during the reporting period. Actual results could differ from those estimates. | |||||||||||||||||
| Futures Contracts | |||||||||||||||||
| The Fund invests in commodity futures contracts. Upon execution of a futures contract, the Fund is obligated to deposit cash or eligible securities, also known as “initial margin,” into an account at its clearing broker. Generally investments in futures contracts also obligate the investor and the clearing broker to settle monies on a daily basis representing changes in the prior days “mark-to-market” of the open contracts. If the investor has unrealized appreciation the clearing broker would credit the investors account with an amount equal to appreciation and conversely if the investor has unrealized depreciation the clearing broker would debit the investors account with an amount equal to depreciation. These daily cash settlements are also known as “variation margin.” In lieu of posting variation margin daily, the Fund has deposited cash with the clearing broker, generally representing approximately twice the required initial margin to cover the initial margin and the daily changes in the market value of its futures investments. Cash held by the clearing broker to cover both margin requirements on open futures contracts is recognized as “Deposits with brokers” on the Statements of Financial Condition. | |||||||||||||||||
| During the period the futures contract is open, changes in the value of the contract are recognized as an unrealized gain or loss by “marking-to-market” on a daily basis to reflect the changes in market value of the contract, which are recognized as a component of “Unrealized appreciation or depreciation on futures contracts” on the Statements of Financial Condition and “Change in net unrealized appreciation (depreciation) of futures contracts” on the Statements of Operations. When the contract is closed, the Fund records a realized gain or loss equal to the difference between the value of the contract on the closing date and the value of the contract when originally entered into, which is recognized as a component of “Net realized gain (loss) from futures contracts” on the Statements of Operations. | |||||||||||||||||
| Risks of investments in commodity futures contracts include possible adverse movement in the price of the commodities underlying the contracts, the possibility that there may not be a liquid secondary market for the contracts and the possibility that a change in the value of the contract may not correlate with a change in the value of the underlying commodities. | |||||||||||||||||
| The average number of long and short futures contracts outstanding during the nine months ended September 30, 2013 and the period October 31, 2012 (date on which the Fund began entering into futures contracts) through December 31, 2012 was as follows: | |||||||||||||||||
| Nine Months Ended | For the Period | ||||||||||||||||
| September 30, 2013 | 31-Oct-12 | ||||||||||||||||
| through | |||||||||||||||||
| December 31, 2012 | |||||||||||||||||
| Average number of long and short futures contracts outstanding* | 5,539 | 5,255 | |||||||||||||||
| * | The average number of contracts is calculated based on the absolute aggregate number of contracts outstanding at the beginning of the fiscal year and at the end of each quarter within the current fiscal year. For the period October 31, 2012 through December 31, 2012, the average number of contracts is calculated based on the absolute aggregate number of contracts outstanding at the beginning of the period and at the end of each month within the remainder of the period. | ||||||||||||||||
| Refer to Note 3 – Derivative Instruments and Hedging Activities within these Notes to Financial Statements for further details on futures contract activity. | |||||||||||||||||
| Options Contracts | |||||||||||||||||
| The Fund may write (sell) and purchase options on commodity futures contracts to enhance the Fund’s risk-adjusted total return. When the Fund writes an option, an amount equal to the premium received is recognized as a component of “Options written, at value” on the Statements of Financial Condition and is subsequently adjusted to reflect the current value of the written option until the option expires or the Fund enters into a closing purchase transaction. The changes in value of the options written during the reporting period are recognized as a component of “Change in net unrealized appreciation (depreciation) of options written” on the Statements of Operations. When an option is exercised or expires, or the Fund enters into a closing purchase transaction, the difference between the net premium received and any amount paid at expiration or on executing a closing purchase transaction is recognized as a component of “Net realized gain (loss) from options written” on the Statements of Operations. The Fund, as writer of an option, has no control over whether the underlying instrument may be sold (called) and as a result bears the risk of an unfavorable change in the market value of the instrument underlying the written option. There is also the risk the Fund may not be able to enter into a closing transaction because of an illiquid market. During the nine months ended September 30, 2013 and the period November 1, 2012 (date on which the Fund began entering into option contracts) through December 31, 2012 the Fund wrote call and put options on futures contracts. | |||||||||||||||||
| The Fund did not purchase options on futures contracts during the nine months ended September 30, 2013 and the period October 25, 2012 (commencement of operations) through December 31, 2012. The purchase of options involves the risk of loss of all or part of the cash paid for the options (the premium). The market risk associated with purchasing options is limited to the premium paid. The counterparty credit risk of purchasing options, however, needs to take into account the current value of the option, as this is the performance expected from the counterparty. | |||||||||||||||||
| Transactions in both call and put options written were as follows: | |||||||||||||||||
| Nine Months Ended | For the Period | ||||||||||||||||
| 30-Sep-13 | 1-Nov-12 | ||||||||||||||||
| through | |||||||||||||||||
| 31-Dec-12 | |||||||||||||||||
| Number of | Premiums | Number of | Premiums | ||||||||||||||
| Contracts | Received | Contracts | Received | ||||||||||||||
| Outstanding, beginning of period | 1,024 | $ | 4,747,719 | — | $ | — | |||||||||||
| Options written | 5,564 | 28,263,262 | 2,228 | 9,526,927 | |||||||||||||
| Options terminated in closing purchase transactions | (823 | ) | (4,233,653 | ) | (1,110 | ) | (4,375,188 | ) | |||||||||
| Options expired | (1,237 | ) | (5,047,570 | ) | (62 | ) | (213,570 | ) | |||||||||
| Options exercised | (3,641 | ) | (18,333,594 | ) | (32 | ) | (190,450 | ) | |||||||||
| Outstanding, end of the period | 887 | $ | 5,396,164 | 1,024 | $ | 4,747,719 | |||||||||||
| The average number of options written outstanding during the nine months ended September 30, 2013 and the period November 1, 2012 (date on which the Fund began entering into options contracts) through December 31, 2012 was as follows: | |||||||||||||||||
| Nine Months Ended | For the Period | ||||||||||||||||
| September 30, 2013 | November 1, 2012 | ||||||||||||||||
| through | |||||||||||||||||
| December 31, 2012 | |||||||||||||||||
| Average number of options written outstanding* | 916 | 709 | |||||||||||||||
| * | The average number of contracts is calculated based on the outstanding number of contracts at the beginning of the fiscal year and at the end of each quarter within the current fiscal year. For the period November 1, 2012 through December 31, 2012, the average number of contracts is calculated based on the outstanding number of contracts at the beginning of the period and at the end of each month within the remainder of the period. | ||||||||||||||||
| Refer to Note 3 – Derivative Instruments and Hedging Activities within these Notes to Financial Statements for further details on options activity. | |||||||||||||||||
| Netting Agreements | |||||||||||||||||
| In the ordinary course of business, the Fund has entered into transactions subject to enforceable master repurchase agreements or other similar arrangements (“netting agreements”). Generally, the right to offset in netting agreements allows the Fund to offset any exposure to a specific counterparty with any collateral received or delivered to that counterparty based on the terms of the agreements. The Fund manages its cash collateral and securities collateral on a counterparty basis. As of September 30, 2013, the Fund was not invested in any portfolio securities or derivatives, other than the repurchase agreements further described below that are subject to netting agreements. | |||||||||||||||||
| Repurchase Agreements | |||||||||||||||||
| In connection with transactions in repurchase agreements, it is the Fund’s policy that its custodian take possession of the underlying collateral securities, the fair value of which exceeds the principal amount of the repurchase transaction, including accrued interest, at all times. If the counterparty defaults, and the fair value of the collateral declines, realization of the collateral may be delayed or limited. | |||||||||||||||||
| The following table presents the repurchase agreements for the Fund, presented on the Statements of Financial Condition and recognized as a component of “Short-term investments, at value,” that are subject to netting agreements, and the collateral delivered related to those repurchase agreements. As of September 30, 2013, the Fund was not invested in any portfolio securities or derivatives, other than the repurchase agreements further described below, that are subject to netting agreements. The Fund was not invested in repurchase agreements as of December 31, 2012. | |||||||||||||||||
| 30-Sep-13 | |||||||||||||||||
| Counterparty | Short-Term | Collateral Pledged | Net | ||||||||||||||
| Investments, at | (From) | Exposure | |||||||||||||||
| Value | Counterparty* | ||||||||||||||||
| Repurchase Agreements | State Street Bank | $ | 3,072,680 | $ | (3,072,680 | ) | $ | — | |||||||||
| * | As of September 30, 2013, the value of the collateral pledged from the counterparty exceeded the value of the repurchase agreements. Refer to the Schedule of Investments for details on the repurchase agreements. | ||||||||||||||||
| Collateral Investments | |||||||||||||||||
| Currently, approximately 15% of the Fund’s net assets are committed to secure the Fund’s futures contract positions. These assets are placed in a commodity futures account maintained by the Fund’s clearing broker, and are held in high-quality instruments permitted under CFTC regulations. | |||||||||||||||||
| The Fund’s remaining assets are held in a separate collateral investment account managed by the Collateral Sub-advisor. The Fund’s assets held in the separate collateral account are invested in cash equivalents, U.S. government securities and other high-quality short-term debt securities with final terms not exceeding one year at the time of investment. The portfolio’s debt securities (other than U.S. government securities) are rated at the highest applicable rating as determined by at least one nationally recognized statistical rating organization, or if unrated, judged by the Collateral Sub-advisor to be of comparable quality. | |||||||||||||||||
| Investment Valuation | |||||||||||||||||
| Commodity futures contracts and options on commodity futures contracts traded on an exchange will be valued at the final settlement price or official closing price as determined by the principal exchange on which the instruments are traded as supplied by independent pricing services. These investments are generally classified as Level 1 for fair value measurement purposes. Over-the-counter commodity futures contracts and options on commodity futures contracts not traded on an exchange will be valued, in order of hierarchy, by independent pricing services, price quotations obtained from counterparty broker-dealers, or through fair valuation methodologies as determined by the Manager. These investments are generally classified as Level 2. Additionally, events may occur after the close of the market, but prior to the determination of the Fund’s net asset value, that may affect the values of the Fund’s investments. In such circumstances, the Manager will determine a fair valuation for such investments that in its opinion is reflective of fair market value. These investments are generally classified as Level 2 or Level 3 depending on the priority of the significant inputs. | |||||||||||||||||
| Prices of fixed-income securities, including, but not limited to, highly rated agency discount notes and U.S. Treasury bills, are provided by a pricing service approved by the Fund’s Manager. These securities are generally classified as Level 2. The pricing service establishes a security’s fair value using methods that may include consideration of the following: yields or prices of investments of comparable quality, type of issue, coupon, maturity and rating, market quotes or indications of value from security dealers, evaluations of anticipated cash flows or collateral, general market conditions and other information and analysis, including the obligor’s credit characteristics considered relevant. These securities are generally classified as Level 2 or Level 3 depending on the priority of the significant inputs. | |||||||||||||||||
| Repurchase agreements are valued at contract amount plus accrued interest, which approximates market value. These securities are generally classified as Level 2. | |||||||||||||||||
| Fair Value Measurements | |||||||||||||||||
| Fair value is defined as the price that the Fund would receive upon selling an investment or transferring a liability in an orderly transaction to an independent buyer in the principal or most advantageous market for the investment. A three-tier hierarchy is used to maximize the use of observable market data and minimize the use of unobservable inputs and to establish classification of fair value measurements for disclosure purposes. Observable inputs reflect the assumptions market participants would use in pricing the asset or liability. Observable inputs are based on market data obtained from sources independent of the reporting entity. Unobservable inputs reflect the reporting entity’s own assumptions about the assumptions market participants would use in pricing the asset or liability. Unobservable inputs are based on the best information available in the circumstances. The following is a summary of the three-tier hierarchy of valuation inputs. | |||||||||||||||||
| Level 1—Inputs are unadjusted and prices are determined by quoted prices in active markets for identical securities. | |||||||||||||||||
| Level 2—Prices are determined using other significant observable inputs (including quoted prices for similar securities, interest rates, prepayment speeds, credit risk, etc.). | |||||||||||||||||
| Level 3—Prices are determined using significant unobservable inputs (including management’s assumptions in determining the fair value of investments). | |||||||||||||||||
| The inputs or methodologies used for valuing securities are not an indication of the risks associated with investing in those securities. The following is a summary of the Fund’s fair value measurements as of September 30, 2013 and December 31, 2012: | |||||||||||||||||
| 30-Sep-13 | |||||||||||||||||
| Level 1 | Level 2 | Level 3 | Total | ||||||||||||||
| Short-Term Investments: | |||||||||||||||||
| U.S. Government and Agency Obligations | $ | — | $ | 329,171,513 | $ | — | $ | 329,171,513 | |||||||||
| Repurchase Agreements | — | 3,072,680 | — | 3,072,680 | |||||||||||||
| Derivatives: | |||||||||||||||||
| Futures Contracts* | (805,361 | ) | — | — | (805,361 | ) | |||||||||||
| Options Written | (5,486,327 | ) | — | — | (5,486,327 | ) | |||||||||||
| Total | $ | (6,291,688 | ) | $ | 332,244,193 | $ | — | $ | 325,952,505 | ||||||||
| 31-Dec-12 | |||||||||||||||||
| Level 1 | Level 2 | Level 3 | Total | ||||||||||||||
| Short-Term Investments: | |||||||||||||||||
| U.S. Government and Agency Obligations | $ | — | $ | 372,303,955 | $ | — | $ | 372,303,955 | |||||||||
| Derivatives: | |||||||||||||||||
| Futures Contracts* | (3,255,655 | ) | — | — | (3,255,655 | ) | |||||||||||
| Options Written | (3,465,424 | ) | — | — | (3,465,424 | ) | |||||||||||
| Total | $ | (6,721,079 | ) | $ | 372,303,955 | $ | — | $ | 365,582,876 | ||||||||
| * | Represents net unrealized appreciation (depreciation) as reported in the Schedule of Investments as of the end of each reporting period. | ||||||||||||||||
| The Manager is responsible for the Fund’s valuation process and has delegated daily oversight of the process to the Manager’s Valuation Committee. The Valuation Committee, pursuant to its valuation policies and procedures, is responsible for making fair value determinations, evaluating the effectiveness of the Fund’s pricing policies, and reporting to the Manager’s senior management. The Valuation Committee is aided in its efforts by the Manager’s Securities Valuation Team, which is responsible for administering the daily valuation process and applying fair value methodologies as approved by the Valuation Committee. When determining the reliability of independent pricing services for investments owned by the Fund, the Valuation Committee, among other things, conducts due diligence reviews of the pricing services and monitors the quality of security prices received through various testing reports conducted by the Securities Valuation Team. | |||||||||||||||||
| For each portfolio instrument that has been fair valued pursuant to the Valuation Committee’s policies, the fair value price is compared against the last available and next available market quotations. The Valuation Committee reviews the results of such testing and fair valuation occurrences are reported to the Manager’s senior management. | |||||||||||||||||
| Investment Transactions | |||||||||||||||||
| Investment transactions are recorded on a trade date basis. Realized gains and losses from investment transactions are determined on the specific identification method, which is the same for federal income tax purposes. | |||||||||||||||||
| Investment Income | |||||||||||||||||
| Interest income, which reflects the amortization of premiums and includes accretion of discounts for financial reporting purposes, is recorded on an accrual basis. | |||||||||||||||||
| Brokerage Commissions and Fees | |||||||||||||||||
| The Fund pays brokerage commissions, including applicable clearing costs, exchange fees, NFA fees, give-up fees, pit brokerage fees and other transaction-related fees and expenses, incurred in connection with its commodity trading activities. | |||||||||||||||||
| Income Taxes | |||||||||||||||||
| No provision for federal, state, and local income taxes has been made in the accompanying financial statements because the Fund has elected to be classified as a partnership for U.S. federal income tax purposes. Each owner of the Fund’s shares will be required to take into account its allocable share of the Fund’s income, gains, losses, deductions and other items for the Fund’s taxable year. | |||||||||||||||||
| For all open tax years and all major taxing jurisdictions, the Manager of the Fund has concluded that there are no significant uncertain tax positions that would require recognition in the financial statements. Open tax years are those that are open for examination by taxing authorities (i.e., generally the last four tax year ends and the interim tax period since then). Furthermore, the Manager of the Fund is also not aware of any tax positions for which it is reasonably possible that the total amounts of unrecognized tax benefits will significantly change in the next twelve months. | |||||||||||||||||
| Expense Recognition | |||||||||||||||||
| All expenses of the Fund are recognized on an accrual basis. The Fund pays all routine and extraordinary costs and expenses of its operations, brokerage expenses, custody fees, transfer agent expenses, professional fees, expenses of preparing, printing and distributing reports, notices, information statements, proxy statements, reports to governmental agencies, and taxes, if any. | |||||||||||||||||
| Organizational Expenses and Offering Costs | |||||||||||||||||
| In connection with the Fund’s initial public offering on October 25, 2012, Nuveen (i) reimbursed all organizational expenses of the Fund and (ii) paid all offering costs (other than sales load and underwriting commissions) that exceeded $.05 per share. The Fund’s share of offering costs ($940,000) was recorded as a reduction of the proceeds from the sale of the shares. These costs are recognized as “Organization expenses” on the Statements of Operations. | |||||||||||||||||
| Calculation of Net Asset Value | |||||||||||||||||
| The net asset value per share of the Fund on any given day is computed by dividing the value of all assets of the Fund (including any accrued interest), less all liabilities (including accrued expenses and distributions declared but unpaid), by the total number of shares outstanding. | |||||||||||||||||
| Distributions | |||||||||||||||||
| The Fund intends to make regular monthly distributions to its shareholders stated in terms of a fixed cents per share distribution rate. Among other factors, the Manager seeks to establish a distribution rate that roughly corresponds to its projections of the total return that could reasonably be expected to be generated by the Fund over an extended period of time. In the event that the amount of income earned or capital gains realized by the Fund is not sufficient to cover the Fund’s distribution the Fund may be required to liquidate investments to fund distributions at times or on terms that are disadvantageous to the Fund and its shareholders. As market conditions and portfolio performance may change, the rate of distribution on the shares and the Fund’s distribution policy could change. The Manager reserves the right to change the Fund’s distribution policy and the basis for establishing the rate of the Fund’s monthly distributions, or may temporarily suspend or reduce distributions without a change in policy, at any time and may do so without prior notice to shareholders. | |||||||||||||||||
| Distributions to shareholders are recorded on the ex-dividend date. | |||||||||||||||||
| Commitments and Contingencies | |||||||||||||||||
| Under the Fund’s organizational documents, the Manager, Wilmington Trust Company (the Fund’s Delaware trustee) and the Manager’s independent committee members are indemnified against certain liabilities arising out of the performance of their duties to the Fund. In addition, in the normal course of business, the Fund enters into contracts that provide general indemnifications to other parties. The Fund’s maximum exposure under these arrangements is unknown, as this would involve future claims that may be made against the Fund that have not yet occurred. However, the Fund believes the risk of loss pursuant to these contracts to be remote. | |||||||||||||||||
| Financial Instrument Risk | |||||||||||||||||
| The Fund utilizes commodity futures and options, whose values are based upon an underlying asset and generally represent future commitments that have a reasonable possibility of being settled in cash or through physical delivery. As of September 30, 2013 and December 31, 2012, the financial instruments held by the Fund were traded on an exchange and are standardized contracts. | |||||||||||||||||
| Market risk is the potential for changes in the value of the financial instruments traded by the Fund due to market changes, including fluctuations in commodity prices. Investing in commodity futures contracts involves the Fund entering into contractual commitments to purchase or sell a particular commodity at a specified date and price. The market risk associated with the Fund’s commitments to purchase commodities will be limited to the gross or face amount of the contracts held. The Fund’s exposure to market risk may be influenced by a number of factors, including changes in international balances of payments and trade, currency devaluations and revaluations, changes in interest and foreign currency exchange rates, price volatility of commodity futures contracts and market liquidity, weather, geopolitical events and other factors. These factors also affect the Fund’s investments in options on commodity futures contracts. The inherent uncertainty of the Fund’s investments as well as the development of drastic market occurrences could ultimately lead to a loss of all, or substantially all, of investors’ capital. | |||||||||||||||||
| Credit risk is the possibility that a loss may occur due to failure of a counterparty performing according to the terms of the futures and option contracts. The Fund may be exposed to credit risk from its investments in commodity futures contracts and options on commodity futures contracts resulting from the clearing house associated with a particular exchange failing to meet its obligations to the Fund. In general, clearing houses are backed by their corporate members who may be required to share in the financial burden resulting from the nonperformance of one of their members, which should significantly reduce this credit risk. In cases where the clearing house is not backed by the clearing members (i.e., as in some foreign exchanges), it may be backed by a consortium of banks or other financial institutions. There can be no assurance that any counterparty, clearing member or clearing house will meet its obligations to the Fund. | |||||||||||||||||
| The Fund is subject to short exposure when it sells short a futures contract or writes a put option. Short sales are transactions in which the Fund initiates a position by selling a futures contract short. A short futures position allows the short seller to profit from declines in the price of the underlying commodity to the extent such declines exceed the transaction costs. In a short sale transaction, the Fund must deliver the underlying commodity at the contract price to a buyer of the contract who stands for delivery under the rules of the exchange that lists the contract or must offset the contract by entering into an opposite and offsetting transaction in the market. Likewise, the writer of a call option is required to deliver the underlying futures contract at the strike price or offset the option by entering into an opposite and offsetting transaction in the market. The price at such time may be higher or lower than the price at which the futures contract was sold short or the strike price of the call option when the option was written. If the underlying price of the futures contract goes down between the time that the Fund sells the contract short and offsets the contract, the Fund will realize a gain on the transaction. If the price of the underlying futures contract drops below the strike price of the call option written, the option will expire worthless and the Fund also will realize a gain to the extent of the option premium received. Conversely, if the price of the underlying short futures contract goes up during the period, the Fund will realize a loss on the transaction. If the price of the underlying futures contract is higher than the strike price of a call option written, the option will become in-the-money and the Fund may realize a loss less any premium received for writing the option. A short sale creates the risk of an unlimited loss since the price of the underlying commodity in a futures contract or the underlying futures contract in a call option written could theoretically increase without limit, thus increasing the cost of covering the short positions. In circumstances where a market has reached its maximum price limits imposed by the exchange, the short seller may be unable to offset its short position until the next trading day, when prices could increase again in rapid trading. | |||||||||||||||||
| The commodity markets have volatility risk. The commodity markets have experienced periods of extreme volatility. General market uncertainty and consequent repricing risk have led to market imbalances of sellers and buyers, which in turn have resulted in significant reductions in values of a variety of commodities. Similar future market conditions may result in rapid and substantial valuation increases or decreases in the Fund’s holdings. In addition, volatility in the commodity and securities markets may directly and adversely affect the setting of distribution rates on the Fund’s shares. | |||||||||||||||||
Derivative_Instruments_and_Hed
| Derivative Instruments and Hedging Activities | 9 Months Ended | ||||||||||||||
| Sep. 30, 2013 | |||||||||||||||
| Derivative Instruments and Hedging Activities | ' | ||||||||||||||
| 3. Derivative Instruments and Hedging Activities | |||||||||||||||
| The Fund records derivative instruments at fair value, with changes in fair value recognized on the Statements of Operations. | |||||||||||||||
| The following tables present the fair value of all derivative instruments held by the Fund, the location of these instruments on the Statements of Financial Condition and the primary underlying risk exposure. | |||||||||||||||
| September 30, 2013 | |||||||||||||||
| Location on the Statements of Financial Condition | |||||||||||||||
| Underlying | Derivative | Asset Derivatives | Liability Derivatives | ||||||||||||
| Risk Exposure | Instrument | Location | Value | Location | Value | ||||||||||
| Commodity | Futures Contracts | Unrealized appreciation on futures contracts | $ | 4,806,535 | Unrealized depreciation on futures contracts | $ | 5,611,896 | ||||||||
| Commodity | Call Options | — | — | Options written, at value | 1,241,933 | ||||||||||
| Commodity | Put Options | — | — | Options written, at value | 4,244,394 | ||||||||||
| Total | $ | 4,806,535 | $ | 11,098,223 | |||||||||||
| 31-Dec-12 | |||||||||||||||
| Location on the Statements of Financial Condition* | |||||||||||||||
| Underlying | Derivative | Asset Derivatives | Liability Derivatives | ||||||||||||
| Risk Exposure | Instrument | Location | Value | Location | Value | ||||||||||
| Commodity | Futures Contracts | Unrealized appreciation on futures contracts | $ | 1,499,470 | Unrealized depreciation on futures contracts | $ | 4,755,125 | ||||||||
| Commodity | Call Options | — | — | Options written, at value | 2,274,790 | ||||||||||
| Commodity | Put Options | — | — | Options written, at value | 1,190,634 | ||||||||||
| Total | $ | 1,499,470 | $ | 8,220,549 | |||||||||||
| * | Amounts have been reclassified to conform to the current presentation. | ||||||||||||||
| The following table presents the amount of net realized gain (loss) and change in net unrealized appreciation (depreciation) recognized on derivative instruments on the Statements of Operations and the primary underlying risk exposure. | |||||||||||||||
| Commodity Risk Exposure | Nine Months Ended | Nine Months Ended | |||||||||||||
| September 30, 2013 | September 30, 2012** | ||||||||||||||
| Net realized gain (loss) from: | |||||||||||||||
| Futures contracts | $ | (36,509,336 | ) | $ | — | ||||||||||
| Call options written | 13,518,540 | — | |||||||||||||
| Put options written | 10,512,300 | — | |||||||||||||
| Change in net unrealized appreciation (depreciation) of: | |||||||||||||||
| Futures contracts | $ | 2,450,294 | $ | — | |||||||||||
| Call options written | (956,876 | ) | — | ||||||||||||
| Put options written | (415,582 | ) | — | ||||||||||||
| ** | The Fund was organized as a statutory trust under Delaware law on May 25, 2011, and commenced operations on October 25, 2012. | ||||||||||||||
Related_Parties
| Related Parties | 9 Months Ended | ||||
| Sep. 30, 2013 | |||||
| Related Parties | ' | ||||
| 4. Related Parties | |||||
| The Manager, the Commodity Sub-advisor and the Collateral Sub-advisor are considered to be related parties to the Fund. | |||||
| For the services and facilities provided by the Manager, the Fund pays the Manager an annual management fee, payable monthly, based on the Fund’s average daily net assets, according to the following schedule: | |||||
| Average Daily Net Assets | Management Fee | ||||
| For the first $500 million | 1.25 | % | |||
| For the next $500 million | 1.225 | ||||
| For the next $500 million | 1.2 | ||||
| For the next $500 million | 1.175 | ||||
| For net assets over $2 billion | 1.15 | ||||
| “Average daily net assets” means the total assets of the Fund, minus the sum of its total liabilities. | |||||
| The Manager and the Fund have entered into sub-advisory agreements with the Commodity Sub-advisor and the Collateral Sub-advisor. Both the Commodity Sub-advisor and the Collateral Sub-advisor are compensated for their services to the Fund from the management fees paid to the Manager, and the Fund does not reimburse the Manager for those fees. | |||||
Share_Repurchase_Program
| Share Repurchase Program | 9 Months Ended | ||||
| Sep. 30, 2013 | |||||
| Share Repurchase Program | ' | ||||
| 5. Share Repurchase Program | |||||
| On March 14, 2013, the Fund adopted an open-market share repurchase program pursuant to which it is authorized to repurchase an aggregate of up to 10% of its outstanding common shares (approximately 1,800,000 shares) in open-market transactions at the Manager’s discretion. | |||||
| Transactions in share repurchases were as follows: | |||||
| Nine Months Ended | |||||
| September 30, 2013 | |||||
| Shares repurchased | 117,500 | ||||
| Weighted average price per share | $ | 17.89 | |||
Financial_Highlights
| Financial Highlights | 9 Months Ended | ||||||||
| Sep. 30, 2013 | |||||||||
| Financial Highlights | ' | ||||||||
| 6. Financial Highlights | |||||||||
| The following financial highlights relate to investment performance and operations for a Fund share outstanding during the three months ended and the nine months ended September 30, 2013. As of September 30, 2012, the Fund had no operations other than those related to organizational matters and therefore there are no financial highlights presented. The Net Asset Value presentation is calculated using average daily shares outstanding. The Ratios to Average Net Assets are calculated using average daily net assets and have been annualized for periods less than a full fiscal year. The Total Returns at Net Asset Value and Market Value are based on the change in net asset value and market value, respectively, for a share during the period. An investor’s return and ratios will vary based on the timing of purchasing and selling Fund shares. | |||||||||
| Three Months Ended | Nine Months Ended | ||||||||
| September 30, 2013 | September 30, 2013 | ||||||||
| Net Asset Value: | |||||||||
| Net asset value per share—beginning of period | $ | 21.11 | $ | 22.72 | |||||
| Net investment income (loss) | (.09 | ) | (.26 | ) | |||||
| Net realized and unrealized gain (loss) | (.08 | ) | (.60 | ) | |||||
| Distributions | (.47 | ) | (1.39 | ) | |||||
| Discount from shares repurchased and retired | 0.01 | 0.01 | |||||||
| Net asset value per share—end of period | $ | 20.48 | $ | 20.48 | |||||
| Market Value: | |||||||||
| Market value per share—beginning of period | 19.87 | $ | 21.22 | ||||||
| Market value per share—end of period | $ | 17.23 | $ | 17.23 | |||||
| Ratios to Average Net Assets:(a) | |||||||||
| Net investment income (loss) | (1.62 | )% | (1.62 | )% | |||||
| Expenses | 1.73 | % | 1.74 | % | |||||
| Total Returns:(b) | |||||||||
| Based on Net Asset Value | (.80 | )% | (3.77 | )% | |||||
| Based on Market Value | (10.99 | )% | (12.80 | )% | |||||
| (a) | Annualized. | ||||||||
| (b) | Total Return Based on Net Asset Value is the combination of changes in net asset value per share and the assumed reinvestment of distributions, if any, at net asset value per share on the distribution payment date. The last distribution declared in the period, which is typically paid on the first business day of the following month, is assumed to be reinvested at the net asset value per share at the end of the period. Total returns are not annualized. | ||||||||
| Total Return Based on Market Value is the combination of changes in the market price per share and the assumed reinvestment of distributions, if any, at the ending market price per share on the distribution payment date. The last distribution declared in the period, which is typically paid on the first business day of the following month, is assumed to be reinvested at the ending market price per share at the end of the period. Total returns are not annualized. | |||||||||
Summary_of_Significant_Account1
| Summary of Significant Accounting Policies (Policies) | 9 Months Ended | ||||||||||||||||
| Sep. 30, 2013 | |||||||||||||||||
| Basis of Accounting | ' | ||||||||||||||||
| Basis of Accounting | |||||||||||||||||
| The accompanying financial statements have been prepared in conformity with U.S. GAAP. The preparation of financial statements in conformity with U.S. GAAP requires management to make certain estimates and assumptions that affect the reported amounts of assets and liabilities and disclosures of contingent assets and liabilities at the date of the financial statements and the reported amounts of increases and decreases in net assets from operations during the reporting period. Actual results could differ from those estimates. | |||||||||||||||||
| Futures Contracts and Options Contracts | ' | ||||||||||||||||
| Futures Contracts | |||||||||||||||||
| The Fund invests in commodity futures contracts. Upon execution of a futures contract, the Fund is obligated to deposit cash or eligible securities, also known as “initial margin,” into an account at its clearing broker. Generally investments in futures contracts also obligate the investor and the clearing broker to settle monies on a daily basis representing changes in the prior days “mark-to-market” of the open contracts. If the investor has unrealized appreciation the clearing broker would credit the investors account with an amount equal to appreciation and conversely if the investor has unrealized depreciation the clearing broker would debit the investors account with an amount equal to depreciation. These daily cash settlements are also known as “variation margin.” In lieu of posting variation margin daily, the Fund has deposited cash with the clearing broker, generally representing approximately twice the required initial margin to cover the initial margin and the daily changes in the market value of its futures investments. Cash held by the clearing broker to cover both margin requirements on open futures contracts is recognized as “Deposits with brokers” on the Statements of Financial Condition. | |||||||||||||||||
| During the period the futures contract is open, changes in the value of the contract are recognized as an unrealized gain or loss by “marking-to-market” on a daily basis to reflect the changes in market value of the contract, which are recognized as a component of “Unrealized appreciation or depreciation on futures contracts” on the Statements of Financial Condition and “Change in net unrealized appreciation (depreciation) of futures contracts” on the Statements of Operations. When the contract is closed, the Fund records a realized gain or loss equal to the difference between the value of the contract on the closing date and the value of the contract when originally entered into, which is recognized as a component of “Net realized gain (loss) from futures contracts” on the Statements of Operations. | |||||||||||||||||
| Risks of investments in commodity futures contracts include possible adverse movement in the price of the commodities underlying the contracts, the possibility that there may not be a liquid secondary market for the contracts and the possibility that a change in the value of the contract may not correlate with a change in the value of the underlying commodities. | |||||||||||||||||
| The average number of long and short futures contracts outstanding during the nine months ended September 30, 2013 and the period October 31, 2012 (date on which the Fund began entering into futures contracts) through December 31, 2012 was as follows: | |||||||||||||||||
| Nine Months Ended | For the Period | ||||||||||||||||
| September 30, 2013 | 31-Oct-12 | ||||||||||||||||
| through | |||||||||||||||||
| December 31, 2012 | |||||||||||||||||
| Average number of long and short futures contracts outstanding* | 5,539 | 5,255 | |||||||||||||||
| * | The average number of contracts is calculated based on the absolute aggregate number of contracts outstanding at the beginning of the fiscal year and at the end of each quarter within the current fiscal year. For the period October 31, 2012 through December 31, 2012, the average number of contracts is calculated based on the absolute aggregate number of contracts outstanding at the beginning of the period and at the end of each month within the remainder of the period. | ||||||||||||||||
| Refer to Note 3 – Derivative Instruments and Hedging Activities within these Notes to Financial Statements for further details on futures contract activity. | |||||||||||||||||
| Options Contracts | |||||||||||||||||
| The Fund may write (sell) and purchase options on commodity futures contracts to enhance the Fund’s risk-adjusted total return. When the Fund writes an option, an amount equal to the premium received is recognized as a component of “Options written, at value” on the Statements of Financial Condition and is subsequently adjusted to reflect the current value of the written option until the option expires or the Fund enters into a closing purchase transaction. The changes in value of the options written during the reporting period are recognized as a component of “Change in net unrealized appreciation (depreciation) of options written” on the Statements of Operations. When an option is exercised or expires, or the Fund enters into a closing purchase transaction, the difference between the net premium received and any amount paid at expiration or on executing a closing purchase transaction is recognized as a component of “Net realized gain (loss) from options written” on the Statements of Operations. The Fund, as writer of an option, has no control over whether the underlying instrument may be sold (called) and as a result bears the risk of an unfavorable change in the market value of the instrument underlying the written option. There is also the risk the Fund may not be able to enter into a closing transaction because of an illiquid market. During the nine months ended September 30, 2013 and the period November 1, 2012 (date on which the Fund began entering into option contracts) through December 31, 2012 the Fund wrote call and put options on futures contracts. | |||||||||||||||||
| The Fund did not purchase options on futures contracts during the nine months ended September 30, 2013 and the period October 25, 2012 (commencement of operations) through December 31, 2012. The purchase of options involves the risk of loss of all or part of the cash paid for the options (the premium). The market risk associated with purchasing options is limited to the premium paid. The counterparty credit risk of purchasing options, however, needs to take into account the current value of the option, as this is the performance expected from the counterparty. | |||||||||||||||||
| Transactions in both call and put options written were as follows: | |||||||||||||||||
| Nine Months Ended | For the Period | ||||||||||||||||
| 30-Sep-13 | 1-Nov-12 | ||||||||||||||||
| through | |||||||||||||||||
| 31-Dec-12 | |||||||||||||||||
| Number of | Premiums | Number of | Premiums | ||||||||||||||
| Contracts | Received | Contracts | Received | ||||||||||||||
| Outstanding, beginning of period | 1,024 | $ | 4,747,719 | — | $ | — | |||||||||||
| Options written | 5,564 | 28,263,262 | 2,228 | 9,526,927 | |||||||||||||
| Options terminated in closing purchase transactions | (823 | ) | (4,233,653 | ) | (1,110 | ) | (4,375,188 | ) | |||||||||
| Options expired | (1,237 | ) | (5,047,570 | ) | (62 | ) | (213,570 | ) | |||||||||
| Options exercised | (3,641 | ) | (18,333,594 | ) | (32 | ) | (190,450 | ) | |||||||||
| Outstanding, end of the period | 887 | $ | 5,396,164 | 1,024 | $ | 4,747,719 | |||||||||||
| The average number of options written outstanding during the nine months ended September 30, 2013 and the period November 1, 2012 (date on which the Fund began entering into options contracts) through December 31, 2012 was as follows: | |||||||||||||||||
| Nine Months Ended | For the Period | ||||||||||||||||
| September 30, 2013 | November 1, 2012 | ||||||||||||||||
| through | |||||||||||||||||
| December 31, 2012 | |||||||||||||||||
| Average number of options written outstanding* | 916 | 709 | |||||||||||||||
| * | The average number of contracts is calculated based on the outstanding number of contracts at the beginning of the fiscal year and at the end of each quarter within the current fiscal year. For the period November 1, 2012 through December 31, 2012, the average number of contracts is calculated based on the outstanding number of contracts at the beginning of the period and at the end of each month within the remainder of the period. | ||||||||||||||||
| Refer to Note 3 – Derivative Instruments and Hedging Activities within these Notes to Financial Statements for further details on options activity. | |||||||||||||||||
| Netting Agreements | ' | ||||||||||||||||
| Netting Agreements | |||||||||||||||||
| In the ordinary course of business, the Fund has entered into transactions subject to enforceable master repurchase agreements or other similar arrangements (“netting agreements”). Generally, the right to offset in netting agreements allows the Fund to offset any exposure to a specific counterparty with any collateral received or delivered to that counterparty based on the terms of the agreements. The Fund manages its cash collateral and securities collateral on a counterparty basis. As of September 30, 2013, the Fund was not invested in any portfolio securities or derivatives, other than the repurchase agreements further described below that are subject to netting agreements. | |||||||||||||||||
| Repurchase Agreements | ' | ||||||||||||||||
| Repurchase Agreements | |||||||||||||||||
| In connection with transactions in repurchase agreements, it is the Fund’s policy that its custodian take possession of the underlying collateral securities, the fair value of which exceeds the principal amount of the repurchase transaction, including accrued interest, at all times. If the counterparty defaults, and the fair value of the collateral declines, realization of the collateral may be delayed or limited. | |||||||||||||||||
| The following table presents the repurchase agreements for the Fund, presented on the Statements of Financial Condition and recognized as a component of “Short-term investments, at value,” that are subject to netting agreements, and the collateral delivered related to those repurchase agreements. As of September 30, 2013, the Fund was not invested in any portfolio securities or derivatives, other than the repurchase agreements further described below, that are subject to netting agreements. The Fund was not invested in repurchase agreements as of December 31, 2012. | |||||||||||||||||
| 30-Sep-13 | |||||||||||||||||
| Counterparty | Short-Term | Collateral Pledged | Net | ||||||||||||||
| Investments, at | (From) | Exposure | |||||||||||||||
| Value | Counterparty* | ||||||||||||||||
| Repurchase Agreements | State Street Bank | $ | 3,072,680 | $ | (3,072,680 | ) | $ | — | |||||||||
| * | As of September 30, 2013, the value of the collateral pledged from the counterparty exceeded the value of the repurchase agreements. Refer to the Schedule of Investments for details on the repurchase agreements. | ||||||||||||||||
| Collateral Investments | ' | ||||||||||||||||
| Collateral Investments | |||||||||||||||||
| Currently, approximately 15% of the Fund’s net assets are committed to secure the Fund’s futures contract positions. These assets are placed in a commodity futures account maintained by the Fund’s clearing broker, and are held in high-quality instruments permitted under CFTC regulations. | |||||||||||||||||
| The Fund’s remaining assets are held in a separate collateral investment account managed by the Collateral Sub-advisor. The Fund’s assets held in the separate collateral account are invested in cash equivalents, U.S. government securities and other high-quality short-term debt securities with final terms not exceeding one year at the time of investment. The portfolio’s debt securities (other than U.S. government securities) are rated at the highest applicable rating as determined by at least one nationally recognized statistical rating organization, or if unrated, judged by the Collateral Sub-advisor to be of comparable quality. | |||||||||||||||||
| Investment Valuation | ' | ||||||||||||||||
| Investment Valuation | |||||||||||||||||
| Commodity futures contracts and options on commodity futures contracts traded on an exchange will be valued at the final settlement price or official closing price as determined by the principal exchange on which the instruments are traded as supplied by independent pricing services. These investments are generally classified as Level 1 for fair value measurement purposes. Over-the-counter commodity futures contracts and options on commodity futures contracts not traded on an exchange will be valued, in order of hierarchy, by independent pricing services, price quotations obtained from counterparty broker-dealers, or through fair valuation methodologies as determined by the Manager. These investments are generally classified as Level 2. Additionally, events may occur after the close of the market, but prior to the determination of the Fund’s net asset value, that may affect the values of the Fund’s investments. In such circumstances, the Manager will determine a fair valuation for such investments that in its opinion is reflective of fair market value. These investments are generally classified as Level 2 or Level 3 depending on the priority of the significant inputs. | |||||||||||||||||
| Prices of fixed-income securities, including, but not limited to, highly rated agency discount notes and U.S. Treasury bills, are provided by a pricing service approved by the Fund’s Manager. These securities are generally classified as Level 2. The pricing service establishes a security’s fair value using methods that may include consideration of the following: yields or prices of investments of comparable quality, type of issue, coupon, maturity and rating, market quotes or indications of value from security dealers, evaluations of anticipated cash flows or collateral, general market conditions and other information and analysis, including the obligor’s credit characteristics considered relevant. These securities are generally classified as Level 2 or Level 3 depending on the priority of the significant inputs. | |||||||||||||||||
| Repurchase agreements are valued at contract amount plus accrued interest, which approximates market value. These securities are generally classified as Level 2. | |||||||||||||||||
| Fair Value Measurements | ' | ||||||||||||||||
| Fair Value Measurements | |||||||||||||||||
| Fair value is defined as the price that the Fund would receive upon selling an investment or transferring a liability in an orderly transaction to an independent buyer in the principal or most advantageous market for the investment. A three-tier hierarchy is used to maximize the use of observable market data and minimize the use of unobservable inputs and to establish classification of fair value measurements for disclosure purposes. Observable inputs reflect the assumptions market participants would use in pricing the asset or liability. Observable inputs are based on market data obtained from sources independent of the reporting entity. Unobservable inputs reflect the reporting entity’s own assumptions about the assumptions market participants would use in pricing the asset or liability. Unobservable inputs are based on the best information available in the circumstances. The following is a summary of the three-tier hierarchy of valuation inputs. | |||||||||||||||||
| Level 1—Inputs are unadjusted and prices are determined by quoted prices in active markets for identical securities. | |||||||||||||||||
| Level 2—Prices are determined using other significant observable inputs (including quoted prices for similar securities, interest rates, prepayment speeds, credit risk, etc.). | |||||||||||||||||
| Level 3—Prices are determined using significant unobservable inputs (including management’s assumptions in determining the fair value of investments). | |||||||||||||||||
| The inputs or methodologies used for valuing securities are not an indication of the risks associated with investing in those securities. The following is a summary of the Fund’s fair value measurements as of September 30, 2013 and December 31, 2012: | |||||||||||||||||
| 30-Sep-13 | |||||||||||||||||
| Level 1 | Level 2 | Level 3 | Total | ||||||||||||||
| Short-Term Investments: | |||||||||||||||||
| U.S. Government and Agency Obligations | $ | — | $ | 329,171,513 | $ | — | $ | 329,171,513 | |||||||||
| Repurchase Agreements | — | 3,072,680 | — | 3,072,680 | |||||||||||||
| Derivatives: | |||||||||||||||||
| Futures Contracts* | (805,361 | ) | — | — | (805,361 | ) | |||||||||||
| Options Written | (5,486,327 | ) | — | — | (5,486,327 | ) | |||||||||||
| Total | $ | (6,291,688 | ) | $ | 332,244,193 | $ | — | $ | 325,952,505 | ||||||||
| 31-Dec-12 | |||||||||||||||||
| Level 1 | Level 2 | Level 3 | Total | ||||||||||||||
| Short-Term Investments: | |||||||||||||||||
| U.S. Government and Agency Obligations | $ | — | $ | 372,303,955 | $ | — | $ | 372,303,955 | |||||||||
| Derivatives: | |||||||||||||||||
| Futures Contracts* | (3,255,655 | ) | — | — | (3,255,655 | ) | |||||||||||
| Options Written | (3,465,424 | ) | — | — | (3,465,424 | ) | |||||||||||
| Total | $ | (6,721,079 | ) | $ | 372,303,955 | $ | — | $ | 365,582,876 | ||||||||
| * | Represents net unrealized appreciation (depreciation) as reported in the Schedule of Investments as of the end of each reporting period. | ||||||||||||||||
| The Manager is responsible for the Fund’s valuation process and has delegated daily oversight of the process to the Manager’s Valuation Committee. The Valuation Committee, pursuant to its valuation policies and procedures, is responsible for making fair value determinations, evaluating the effectiveness of the Fund’s pricing policies, and reporting to the Manager’s senior management. The Valuation Committee is aided in its efforts by the Manager’s Securities Valuation Team, which is responsible for administering the daily valuation process and applying fair value methodologies as approved by the Valuation Committee. When determining the reliability of independent pricing services for investments owned by the Fund, the Valuation Committee, among other things, conducts due diligence reviews of the pricing services and monitors the quality of security prices received through various testing reports conducted by the Securities Valuation Team. | |||||||||||||||||
| For each portfolio instrument that has been fair valued pursuant to the Valuation Committee’s policies, the fair value price is compared against the last available and next available market quotations. The Valuation Committee reviews the results of such testing and fair valuation occurrences are reported to the Manager’s senior management. | |||||||||||||||||
| Investment Transactions | ' | ||||||||||||||||
| Investment Transactions | |||||||||||||||||
| Investment transactions are recorded on a trade date basis. Realized gains and losses from investment transactions are determined on the specific identification method, which is the same for federal income tax purposes. | |||||||||||||||||
| Investment Income | ' | ||||||||||||||||
| Investment Income | |||||||||||||||||
| Interest income, which reflects the amortization of premiums and includes accretion of discounts for financial reporting purposes, is recorded on an accrual basis. | |||||||||||||||||
| Brokerage Commissions and Fees | ' | ||||||||||||||||
| Brokerage Commissions and Fees | |||||||||||||||||
| The Fund pays brokerage commissions, including applicable clearing costs, exchange fees, NFA fees, give-up fees, pit brokerage fees and other transaction-related fees and expenses, incurred in connection with its commodity trading activities. | |||||||||||||||||
| Income Taxes | ' | ||||||||||||||||
| Income Taxes | |||||||||||||||||
| No provision for federal, state, and local income taxes has been made in the accompanying financial statements because the Fund has elected to be classified as a partnership for U.S. federal income tax purposes. Each owner of the Fund’s shares will be required to take into account its allocable share of the Fund’s income, gains, losses, deductions and other items for the Fund’s taxable year. | |||||||||||||||||
| For all open tax years and all major taxing jurisdictions, the Manager of the Fund has concluded that there are no significant uncertain tax positions that would require recognition in the financial statements. Open tax years are those that are open for examination by taxing authorities (i.e., generally the last four tax year ends and the interim tax period since then). Furthermore, the Manager of the Fund is also not aware of any tax positions for which it is reasonably possible that the total amounts of unrecognized tax benefits will significantly change in the next twelve months. | |||||||||||||||||
| Expense Recognition | ' | ||||||||||||||||
| Expense Recognition | |||||||||||||||||
| All expenses of the Fund are recognized on an accrual basis. The Fund pays all routine and extraordinary costs and expenses of its operations, brokerage expenses, custody fees, transfer agent expenses, professional fees, expenses of preparing, printing and distributing reports, notices, information statements, proxy statements, reports to governmental agencies, and taxes, if any. | |||||||||||||||||
| Organizational Expenses and Offering Costs | ' | ||||||||||||||||
| Organizational Expenses and Offering Costs | |||||||||||||||||
| In connection with the Fund’s initial public offering on October 25, 2012, Nuveen (i) reimbursed all organizational expenses of the Fund and (ii) paid all offering costs (other than sales load and underwriting commissions) that exceeded $.05 per share. The Fund’s share of offering costs ($940,000) was recorded as a reduction of the proceeds from the sale of the shares. These costs are recognized as “Organization expenses” on the Statements of Operations. | |||||||||||||||||
| Calculation of Net Asset Value | ' | ||||||||||||||||
| Calculation of Net Asset Value | |||||||||||||||||
| The net asset value per share of the Fund on any given day is computed by dividing the value of all assets of the Fund (including any accrued interest), less all liabilities (including accrued expenses and distributions declared but unpaid), by the total number of shares outstanding. | |||||||||||||||||
| Distributions | ' | ||||||||||||||||
| Distributions | |||||||||||||||||
| The Fund intends to make regular monthly distributions to its shareholders stated in terms of a fixed cents per share distribution rate. Among other factors, the Manager seeks to establish a distribution rate that roughly corresponds to its projections of the total return that could reasonably be expected to be generated by the Fund over an extended period of time. In the event that the amount of income earned or capital gains realized by the Fund is not sufficient to cover the Fund’s distribution the Fund may be required to liquidate investments to fund distributions at times or on terms that are disadvantageous to the Fund and its shareholders. As market conditions and portfolio performance may change, the rate of distribution on the shares and the Fund’s distribution policy could change. The Manager reserves the right to change the Fund’s distribution policy and the basis for establishing the rate of the Fund’s monthly distributions, or may temporarily suspend or reduce distributions without a change in policy, at any time and may do so without prior notice to shareholders. | |||||||||||||||||
| Distributions to shareholders are recorded on the ex-dividend date. | |||||||||||||||||
| Commitments and Contingencies | ' | ||||||||||||||||
| Commitments and Contingencies | |||||||||||||||||
| Under the Fund’s organizational documents, the Manager, Wilmington Trust Company (the Fund’s Delaware trustee) and the Manager’s independent committee members are indemnified against certain liabilities arising out of the performance of their duties to the Fund. In addition, in the normal course of business, the Fund enters into contracts that provide general indemnifications to other parties. The Fund’s maximum exposure under these arrangements is unknown, as this would involve future claims that may be made against the Fund that have not yet occurred. However, the Fund believes the risk of loss pursuant to these contracts to be remote. | |||||||||||||||||
| Financial Instrument Risk | ' | ||||||||||||||||
| Financial Instrument Risk | |||||||||||||||||
| The Fund utilizes commodity futures and options, whose values are based upon an underlying asset and generally represent future commitments that have a reasonable possibility of being settled in cash or through physical delivery. As of September 30, 2013 and December 31, 2012, the financial instruments held by the Fund were traded on an exchange and are standardized contracts. | |||||||||||||||||
| Market risk is the potential for changes in the value of the financial instruments traded by the Fund due to market changes, including fluctuations in commodity prices. Investing in commodity futures contracts involves the Fund entering into contractual commitments to purchase or sell a particular commodity at a specified date and price. The market risk associated with the Fund’s commitments to purchase commodities will be limited to the gross or face amount of the contracts held. The Fund’s exposure to market risk may be influenced by a number of factors, including changes in international balances of payments and trade, currency devaluations and revaluations, changes in interest and foreign currency exchange rates, price volatility of commodity futures contracts and market liquidity, weather, geopolitical events and other factors. These factors also affect the Fund’s investments in options on commodity futures contracts. The inherent uncertainty of the Fund’s investments as well as the development of drastic market occurrences could ultimately lead to a loss of all, or substantially all, of investors’ capital. | |||||||||||||||||
| Credit risk is the possibility that a loss may occur due to failure of a counterparty performing according to the terms of the futures and option contracts. The Fund may be exposed to credit risk from its investments in commodity futures contracts and options on commodity futures contracts resulting from the clearing house associated with a particular exchange failing to meet its obligations to the Fund. In general, clearing houses are backed by their corporate members who may be required to share in the financial burden resulting from the nonperformance of one of their members, which should significantly reduce this credit risk. In cases where the clearing house is not backed by the clearing members (i.e., as in some foreign exchanges), it may be backed by a consortium of banks or other financial institutions. There can be no assurance that any counterparty, clearing member or clearing house will meet its obligations to the Fund. | |||||||||||||||||
| The Fund is subject to short exposure when it sells short a futures contract or writes a put option. Short sales are transactions in which the Fund initiates a position by selling a futures contract short. A short futures position allows the short seller to profit from declines in the price of the underlying commodity to the extent such declines exceed the transaction costs. In a short sale transaction, the Fund must deliver the underlying commodity at the contract price to a buyer of the contract who stands for delivery under the rules of the exchange that lists the contract or must offset the contract by entering into an opposite and offsetting transaction in the market. Likewise, the writer of a call option is required to deliver the underlying futures contract at the strike price or offset the option by entering into an opposite and offsetting transaction in the market. The price at such time may be higher or lower than the price at which the futures contract was sold short or the strike price of the call option when the option was written. If the underlying price of the futures contract goes down between the time that the Fund sells the contract short and offsets the contract, the Fund will realize a gain on the transaction. If the price of the underlying futures contract drops below the strike price of the call option written, the option will expire worthless and the Fund also will realize a gain to the extent of the option premium received. Conversely, if the price of the underlying short futures contract goes up during the period, the Fund will realize a loss on the transaction. If the price of the underlying futures contract is higher than the strike price of a call option written, the option will become in-the-money and the Fund may realize a loss less any premium received for writing the option. A short sale creates the risk of an unlimited loss since the price of the underlying commodity in a futures contract or the underlying futures contract in a call option written could theoretically increase without limit, thus increasing the cost of covering the short positions. In circumstances where a market has reached its maximum price limits imposed by the exchange, the short seller may be unable to offset its short position until the next trading day, when prices could increase again in rapid trading. | |||||||||||||||||
| The commodity markets have volatility risk. The commodity markets have experienced periods of extreme volatility. General market uncertainty and consequent repricing risk have led to market imbalances of sellers and buyers, which in turn have resulted in significant reductions in values of a variety of commodities. Similar future market conditions may result in rapid and substantial valuation increases or decreases in the Fund’s holdings. In addition, volatility in the commodity and securities markets may directly and adversely affect the setting of distribution rates on the Fund’s shares. | |||||||||||||||||
Summary_of_Significant_Account2
| Summary of Significant Accounting Policies (Tables) | 9 Months Ended | ||||||||||||||||
| Sep. 30, 2013 | |||||||||||||||||
| Transactions in Call and Put Options | ' | ||||||||||||||||
| Transactions in both call and put options written were as follows: | |||||||||||||||||
| Nine Months Ended | For the Period | ||||||||||||||||
| 30-Sep-13 | 1-Nov-12 | ||||||||||||||||
| through | |||||||||||||||||
| 31-Dec-12 | |||||||||||||||||
| Number of | Premiums | Number of | Premiums | ||||||||||||||
| Contracts | Received | Contracts | Received | ||||||||||||||
| Outstanding, beginning of period | 1,024 | $ | 4,747,719 | — | $ | — | |||||||||||
| Options written | 5,564 | 28,263,262 | 2,228 | 9,526,927 | |||||||||||||
| Options terminated in closing purchase transactions | (823 | ) | (4,233,653 | ) | (1,110 | ) | (4,375,188 | ) | |||||||||
| Options expired | (1,237 | ) | (5,047,570 | ) | (62 | ) | (213,570 | ) | |||||||||
| Options exercised | (3,641 | ) | (18,333,594 | ) | (32 | ) | (190,450 | ) | |||||||||
| Outstanding, end of the period | 887 | $ | 5,396,164 | 1,024 | $ | 4,747,719 | |||||||||||
| Repurchase Agreements for Fund and Collateral of Repurchase Agreements | ' | ||||||||||||||||
| The following table presents the repurchase agreements for the Fund, presented on the Statements of Financial Condition and recognized as a component of “Short-term investments, at value,” that are subject to netting agreements, and the collateral delivered related to those repurchase agreements. As of September 30, 2013, the Fund was not invested in any portfolio securities or derivatives, other than the repurchase agreements further described below, that are subject to netting agreements. The Fund was not invested in repurchase agreements as of December 31, 2012. | |||||||||||||||||
| 30-Sep-13 | |||||||||||||||||
| Counterparty | Short-Term | Collateral Pledged | Net | ||||||||||||||
| Investments, at | (From) | Exposure | |||||||||||||||
| Value | Counterparty* | ||||||||||||||||
| Repurchase Agreements | State Street Bank | $ | 3,072,680 | $ | (3,072,680 | ) | $ | — | |||||||||
| * | As of September 30, 2013, the value of the collateral pledged from the counterparty exceeded the value of the repurchase agreements. Refer to the Schedule of Investments for details on the repurchase agreements. | ||||||||||||||||
| Fair Value Measurements | ' | ||||||||||||||||
| The following is a summary of the Fund’s fair value measurements as of September 30, 2013 and December 31, 2012: | |||||||||||||||||
| 30-Sep-13 | |||||||||||||||||
| Level 1 | Level 2 | Level 3 | Total | ||||||||||||||
| Short-Term Investments: | |||||||||||||||||
| U.S. Government and Agency Obligations | $ | — | $ | 329,171,513 | $ | — | $ | 329,171,513 | |||||||||
| Repurchase Agreements | — | 3,072,680 | — | 3,072,680 | |||||||||||||
| Derivatives: | |||||||||||||||||
| Futures Contracts* | (805,361 | ) | — | — | (805,361 | ) | |||||||||||
| Options Written | (5,486,327 | ) | — | — | (5,486,327 | ) | |||||||||||
| Total | $ | (6,291,688 | ) | $ | 332,244,193 | $ | — | $ | 325,952,505 | ||||||||
| 31-Dec-12 | |||||||||||||||||
| Level 1 | Level 2 | Level 3 | Total | ||||||||||||||
| Short-Term Investments: | |||||||||||||||||
| U.S. Government and Agency Obligations | $ | — | $ | 372,303,955 | $ | — | $ | 372,303,955 | |||||||||
| Derivatives: | |||||||||||||||||
| Futures Contracts* | (3,255,655 | ) | — | — | (3,255,655 | ) | |||||||||||
| Options Written | (3,465,424 | ) | — | — | (3,465,424 | ) | |||||||||||
| Total | $ | (6,721,079 | ) | $ | 372,303,955 | $ | — | $ | 365,582,876 | ||||||||
| * | Represents net unrealized appreciation (depreciation) as reported in the Schedule of Investments as of the end of each reporting period. | ||||||||||||||||
| Futures Contracts | ' | ||||||||||||||||
| Average Number of Contracts Outstanding | ' | ||||||||||||||||
| The average number of long and short futures contracts outstanding during the nine months ended September 30, 2013 and the period October 31, 2012 (date on which the Fund began entering into futures contracts) through December 31, 2012 was as follows: | |||||||||||||||||
| Nine Months Ended | For the Period | ||||||||||||||||
| September 30, 2013 | 31-Oct-12 | ||||||||||||||||
| through | |||||||||||||||||
| December 31, 2012 | |||||||||||||||||
| Average number of long and short futures contracts outstanding* | 5,539 | 5,255 | |||||||||||||||
| * | The average number of contracts is calculated based on the absolute aggregate number of contracts outstanding at the beginning of the fiscal year and at the end of each quarter within the current fiscal year. For the period October 31, 2012 through December 31, 2012, the average number of contracts is calculated based on the absolute aggregate number of contracts outstanding at the beginning of the period and at the end of each month within the remainder of the period. | ||||||||||||||||
| Options Contracts | ' | ||||||||||||||||
| Average Number of Contracts Outstanding | ' | ||||||||||||||||
| The average number of options written outstanding during the nine months ended September 30, 2013 and the period November 1, 2012 (date on which the Fund began entering into options contracts) through December 31, 2012 was as follows: | |||||||||||||||||
| Nine Months Ended | For the Period | ||||||||||||||||
| September 30, 2013 | November 1, 2012 | ||||||||||||||||
| through | |||||||||||||||||
| December 31, 2012 | |||||||||||||||||
| Average number of options written outstanding* | 916 | 709 | |||||||||||||||
| * | The average number of contracts is calculated based on the outstanding number of contracts at the beginning of the fiscal year and at the end of each quarter within the current fiscal year. For the period November 1, 2012 through December 31, 2012, the average number of contracts is calculated based on the outstanding number of contracts at the beginning of the period and at the end of each month within the remainder of the period. | ||||||||||||||||
Derivative_Instruments_and_Hed1
| Derivative Instruments and Hedging Activities (Tables) | 9 Months Ended | ||||||||||||||
| Sep. 30, 2013 | |||||||||||||||
| Fair Value of All Derivative Instruments Held by Fund | ' | ||||||||||||||
| The following tables present the fair value of all derivative instruments held by the Fund, the location of these instruments on the Statements of Financial Condition and the primary underlying risk exposure. | |||||||||||||||
| September 30, 2013 | |||||||||||||||
| Location on the Statements of Financial Condition | |||||||||||||||
| Underlying | Derivative | Asset Derivatives | Liability Derivatives | ||||||||||||
| Risk Exposure | Instrument | Location | Value | Location | Value | ||||||||||
| Commodity | Futures Contracts | Unrealized appreciation on futures contracts | $ | 4,806,535 | Unrealized depreciation on futures contracts | $ | 5,611,896 | ||||||||
| Commodity | Call Options | — | — | Options written, at value | 1,241,933 | ||||||||||
| Commodity | Put Options | — | — | Options written, at value | 4,244,394 | ||||||||||
| Total | $ | 4,806,535 | $ | 11,098,223 | |||||||||||
| 31-Dec-12 | |||||||||||||||
| Location on the Statements of Financial Condition* | |||||||||||||||
| Underlying | Derivative | Asset Derivatives | Liability Derivatives | ||||||||||||
| Risk Exposure | Instrument | Location | Value | Location | Value | ||||||||||
| Commodity | Futures Contracts | Unrealized appreciation on futures contracts | $ | 1,499,470 | Unrealized depreciation on futures contracts | $ | 4,755,125 | ||||||||
| Commodity | Call Options | — | — | Options written, at value | 2,274,790 | ||||||||||
| Commodity | Put Options | — | — | Options written, at value | 1,190,634 | ||||||||||
| Total | $ | 1,499,470 | $ | 8,220,549 | |||||||||||
| * | Amounts have been reclassified to conform to the current presentation. | ||||||||||||||
| Net Realized Gain (Loss) and Change in Net Unrealized Appreciation (Depreciation) Recognized on Derivative Instruments | ' | ||||||||||||||
| The following table presents the amount of net realized gain (loss) and change in net unrealized appreciation (depreciation) recognized on derivative instruments on the Statements of Operations and the primary underlying risk exposure. | |||||||||||||||
| Commodity Risk Exposure | Nine Months Ended | Nine Months Ended | |||||||||||||
| September 30, 2013 | September 30, 2012** | ||||||||||||||
| Net realized gain (loss) from: | |||||||||||||||
| Futures contracts | $ | (36,509,336 | ) | $ | — | ||||||||||
| Call options written | 13,518,540 | — | |||||||||||||
| Put options written | 10,512,300 | — | |||||||||||||
| Change in net unrealized appreciation (depreciation) of: | |||||||||||||||
| Futures contracts | $ | 2,450,294 | $ | — | |||||||||||
| Call options written | (956,876 | ) | — | ||||||||||||
| Put options written | (415,582 | ) | — | ||||||||||||
| ** | The Fund was organized as a statutory trust under Delaware law on May 25, 2011, and commenced operations on October 25, 2012. | ||||||||||||||
Related_Parties_Tables
| Related Parties (Tables) | 9 Months Ended | ||||
| Sep. 30, 2013 | |||||
| Management Fee Paid Based on Funds Average Daily Net Assets | ' | ||||
| For the services and facilities provided by the Manager, the Fund pays the Manager an annual management fee, payable monthly, based on the Fund’s average daily net assets, according to the following schedule: | |||||
| Average Daily Net Assets | Management Fee | ||||
| For the first $500 million | 1.25 | % | |||
| For the next $500 million | 1.225 | ||||
| For the next $500 million | 1.2 | ||||
| For the next $500 million | 1.175 | ||||
| For net assets over $2 billion | 1.15 | ||||
Share_Repurchase_Program_Table
| Share Repurchase Program (Tables) | 9 Months Ended | ||||
| Sep. 30, 2013 | |||||
| Transactions In Share Repurchases | ' | ||||
| Transactions in share repurchases were as follows: | |||||
| Nine Months Ended | |||||
| September 30, 2013 | |||||
| Shares repurchased | 117,500 | ||||
| Weighted average price per share | $ | 17.89 | |||
Financial_Highlights_Tables
| Financial Highlights (Tables) | 9 Months Ended | ||||||||
| Sep. 30, 2013 | |||||||||
| Purchasing and Selling Fund Shares | ' | ||||||||
| An investor’s return and ratios will vary based on the timing of purchasing and selling Fund shares. | |||||||||
| Three Months Ended | Nine Months Ended | ||||||||
| September 30, 2013 | September 30, 2013 | ||||||||
| Net Asset Value: | |||||||||
| Net asset value per share—beginning of period | $ | 21.11 | $ | 22.72 | |||||
| Net investment income (loss) | (.09 | ) | (.26 | ) | |||||
| Net realized and unrealized gain (loss) | (.08 | ) | (.60 | ) | |||||
| Distributions | (.47 | ) | (1.39 | ) | |||||
| Discount from shares repurchased and retired | 0.01 | 0.01 | |||||||
| Net asset value per share—end of period | $ | 20.48 | $ | 20.48 | |||||
| Market Value: | |||||||||
| Market value per share—beginning of period | 19.87 | $ | 21.22 | ||||||
| Market value per share—end of period | $ | 17.23 | $ | 17.23 | |||||
| Ratios to Average Net Assets:(a) | |||||||||
| Net investment income (loss) | (1.62 | )% | (1.62 | )% | |||||
| Expenses | 1.73 | % | 1.74 | % | |||||
| Total Returns:(b) | |||||||||
| Based on Net Asset Value | (.80 | )% | (3.77 | )% | |||||
| Based on Market Value | (10.99 | )% | (12.80 | )% | |||||
| (a) | Annualized. | ||||||||
| (b) | Total Return Based on Net Asset Value is the combination of changes in net asset value per share and the assumed reinvestment of distributions, if any, at net asset value per share on the distribution payment date. The last distribution declared in the period, which is typically paid on the first business day of the following month, is assumed to be reinvested at the net asset value per share at the end of the period. Total returns are not annualized. | ||||||||
Organization_Additional_Inform
| Organization - Additional Information (Detail) (USD $) | 1 Months Ended | |
| Oct. 25, 2012 | Aug. 31, 2011 | |
| Organization [Line Items] | ' | ' |
| Issuance of shares, initial public offering | 18,800,000 | ' |
| Initial capital contribution | ' | $20,055 |
| Organization expenses | $452,000 | ' |
| Issuance of shares | ' | 840 |
| Derivative notional amount as a percentage | 100.00% | ' |
Average_Number_of_Long_and_Sho
| Average Number of Long and Short Futures Contracts Outstanding (Detail) (Futures Contracts) | 2 Months Ended | 9 Months Ended | ||
| Dec. 31, 2012 | Sep. 30, 2013 | |||
| Contract | Contract | |||
| Futures Contracts | ' | ' | ||
| Fair Value, Option, Qualitative Disclosures Related to Election [Line Items] | ' | ' | ||
| Average number of derivative contracts outstanding | 5,255 | [1] | 5,539 | [1] |
| [1] | The average number of contracts is calculated based on the absolute aggregate number of contracts outstanding at the beginning of the fiscal year and at the end of each quarter within the current fiscal year. For the period October 31, 2012 through December 31, 2012, the average number of contracts is calculated based on the absolute aggregate number of contracts outstanding at the beginning of the period and at the end of each month within the remainder of the period. | |||
Transaction_in_Call_and_Put_Op
| Transaction in Call and Put Option (Detail) (USD $) | 2 Months Ended | 9 Months Ended |
| Dec. 31, 2012 | Sep. 30, 2013 | |
| Contract | Contract | |
| Fair Value, Option, Qualitative Disclosures Related to Election [Line Items] | ' | ' |
| Outstanding, end of the period, Premiums Received | $4,747,719 | $5,396,164 |
| Call and Put Option Written | ' | ' |
| Fair Value, Option, Qualitative Disclosures Related to Election [Line Items] | ' | ' |
| Outstanding, beginning of period, Number of Contracts | ' | 1,024 |
| Options written, Number of Contracts | 2,228 | 5,564 |
| Options terminated in closing purchase transactions, Number of Contracts | -1,110 | -823 |
| Options expired, Number of Contracts | -62 | -1,237 |
| Options exercised, Number of Contracts | -32 | -3,641 |
| Outstanding, end of the period, Number of Contracts | 1,024 | 887 |
| Outstanding, beginning of period, Premiums Received | ' | 4,747,719 |
| Options written, Premiums Received | 9,526,927 | 28,263,262 |
| Options terminated in closing purchase transactions, Premiums Received | -4,375,188 | -4,233,653 |
| Options expired, Premiums Received | -213,570 | -5,047,570 |
| Options exercised, Premiums Received | -190,450 | -18,333,594 |
| Outstanding, end of the period, Premiums Received | $4,747,719 | $5,396,164 |
Average_Number_of_Options_Writ
| Average Number of Options Written Outstanding (Detail) (Options Contracts) | 2 Months Ended | 9 Months Ended | ||
| Dec. 31, 2012 | Sep. 30, 2013 | |||
| Contract | Contract | |||
| Options Contracts | ' | ' | ||
| Fair Value, Option, Qualitative Disclosures Related to Election [Line Items] | ' | ' | ||
| Average number of derivative contracts outstanding | 709 | [1] | 916 | [1] |
| [1] | The average number of contracts is calculated based on the outstanding number of contracts at the beginning of the fiscal year and at the end of each quarter within the current fiscal year. For the period November 1, 2012 through December 31, 2012, the average number of contracts is calculated based on the outstanding number of contracts at the beginning of the period and at the end of each month within the remainder of the period. | |||
Repurchase_Agreements_for_Fund
| Repurchase Agreements for Fund and Collateral of Repurchase Agreements (Detail) (USD $) | 9 Months Ended | ||
| Sep. 30, 2013 | Dec. 31, 2012 | ||
| Repurchase Agreement [Line Items] | ' | ' | |
| Counterparty | 'State Street Bank | ' | |
| Short-Term Investments, at Value | $332,244,193 | $372,303,955 | |
| Repurchase Agreements | ' | ' | |
| Repurchase Agreement [Line Items] | ' | ' | |
| Counterparty | 'State Street Bank | ' | |
| Short-Term Investments, at Value | 3,072,680 | ' | |
| Collateral Pledged (From) Counterparty | -3,072,680 | [1] | ' |
| Net Exposure | ' | ' | |
| [1] | As of September 30, 2013, the value of the collateral pledged from the counterparty exceeded the value of the repurchase agreements. Refer to the Schedule of Investments for details on the repurchase agreements. | ||
Summary_of_Significant_Account3
| Summary of Significant Accounting Policies - Additional Information (Detail) (USD $) | 9 Months Ended |
| Sep. 30, 2013 | |
| Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' |
| Percentage of fund's assets committed to secure funds futures and forward contract positions | 15.00% |
| Period of assets invested in cash equivalents | 'Not exceeding one year |
| Offering costs | $0.05 |
| Offering costs as reduction of proceeds from sale of shares | $940,000 |
Summary_of_Funds_Fair_Value_Me
| Summary of Fund's Fair Value Measurements (Detail) (USD $) | Sep. 30, 2013 | Dec. 31, 2012 | ||
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' | ||
| Total | $325,952,505 | $365,582,876 | ||
| Short-term Investments | 332,244,193 | 372,303,955 | ||
| US Government Agencies Debt Securities | ' | ' | ||
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' | ||
| Short-term Investments | 329,171,513 | 372,303,955 | ||
| Futures Contracts | ' | ' | ||
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' | ||
| Net Derivative Fair Value | -805,361 | [1] | -3,255,655 | [1] |
| Options Contracts | ' | ' | ||
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' | ||
| Net Derivative Fair Value | -5,486,327 | -3,465,424 | ||
| Repurchase Agreements | ' | ' | ||
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' | ||
| Short-term Investments | 3,072,680 | ' | ||
| Level 1 | ' | ' | ||
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' | ||
| Total | -6,291,688 | -6,721,079 | ||
| Level 1 | Futures Contracts | ' | ' | ||
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' | ||
| Net Derivative Fair Value | -805,361 | [1] | -3,255,655 | [1] |
| Level 1 | Options Contracts | ' | ' | ||
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' | ||
| Net Derivative Fair Value | -5,486,327 | -3,465,424 | ||
| Level 2 | ' | ' | ||
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' | ||
| Total | 332,244,193 | 372,303,955 | ||
| Level 2 | US Government Agencies Debt Securities | ' | ' | ||
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' | ||
| Short-term Investments | 329,171,513 | 372,303,955 | ||
| Level 2 | Repurchase Agreements | ' | ' | ||
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' | ||
| Short-term Investments | $3,072,680 | ' | ||
| [1] | Represents net unrealized appreciation (depreciation) as reported in the Schedule of Investments as of the end of each reporting period. | |||
Fair_Value_of_Derivative_Instr
| Fair Value of Derivative Instruments Held by Fund (Detail) (Commodity Contract, USD $) | Sep. 30, 2013 | Dec. 31, 2012 | |
| Derivatives, Fair Value [Line Items] | ' | ' | |
| Total Asset Derivatives | $4,806,535 | $1,499,470 | [1] |
| Total Liability Derivatives | 11,098,223 | 8,220,549 | [1] |
| Futures Contracts | ' | ' | |
| Derivatives, Fair Value [Line Items] | ' | ' | |
| Total Asset Derivatives | 4,806,535 | 1,499,470 | [1] |
| Total Liability Derivatives | 5,611,896 | 4,755,125 | [1] |
| Call Option | ' | ' | |
| Derivatives, Fair Value [Line Items] | ' | ' | |
| Total Liability Derivatives | 1,241,933 | 2,274,790 | [1] |
| Put Option | ' | ' | |
| Derivatives, Fair Value [Line Items] | ' | ' | |
| Total Liability Derivatives | $4,244,394 | $1,190,634 | [1] |
| [1] | Amounts have been reclassified to conform to the current presentation. | ||
Net_Realized_Gain_Loss_and_Cha
| Net Realized Gain (Loss) and Change In Net Unrealized Appreciation (Depreciation) Recognized on Derivative Instruments and Primary Underlying Risk Exposure (Detail) (USD $) | 3 Months Ended | 9 Months Ended | 12 Months Ended | |||
| Sep. 30, 2013 | Sep. 30, 2013 | Sep. 30, 2012 | Dec. 31, 2012 | |||
| Net realized gain (loss) from: | ' | ' | ' | ' | ||
| Futures contracts | ' | ($36,509,336) | ' | [1] | ' | |
| Change in net unrealized appreciation (depreciation) of: | ' | ' | ' | ' | ||
| Futures contracts | -14,172,136 | 2,450,294 | ' | [1] | -3,255,655 | [1] |
| Unrealized gain (loss), options written | 855,281 | -1,372,458 | ' | 1,282,295 | [1] | |
| Call Option | Short | ' | ' | ' | ' | ||
| Net realized gain (loss) from: | ' | ' | ' | ' | ||
| Net realized gain (loss), options written | ' | 13,518,540 | ' | [1] | ' | |
| Change in net unrealized appreciation (depreciation) of: | ' | ' | ' | ' | ||
| Unrealized gain (loss), options written | ' | -956,876 | ' | [1] | ' | |
| Put Option | Short | ' | ' | ' | ' | ||
| Net realized gain (loss) from: | ' | ' | ' | ' | ||
| Net realized gain (loss), options written | ' | 10,512,300 | ' | [1] | ' | |
| Change in net unrealized appreciation (depreciation) of: | ' | ' | ' | ' | ||
| Unrealized gain (loss), options written | ' | ($415,582) | ' | [1] | ' | |
| [1] | The Fund was organized as a statutory trust under Delaware law on May 25, 2011, and commenced operations on October 25, 2012. | |||||
Related_Parties_Detail
| Related Parties (Detail) | Sep. 30, 2013 |
| For the first $500 million | ' |
| Management Fees Provided For Service [Line Items] | ' |
| Management Fee Percentage | 1.25% |
| For the next $500 million | ' |
| Management Fees Provided For Service [Line Items] | ' |
| Management Fee Percentage | 1.23% |
| For the next $500 million | ' |
| Management Fees Provided For Service [Line Items] | ' |
| Management Fee Percentage | 1.20% |
| For the next $500 million | ' |
| Management Fees Provided For Service [Line Items] | ' |
| Management Fee Percentage | 1.18% |
| For net assets over $2 billion | ' |
| Management Fees Provided For Service [Line Items] | ' |
| Management Fee Percentage | 1.15% |
Share_Repurchase_Program_Addit
| Share Repurchase Program - Additional Information (Detail) | Mar. 14, 2013 |
| Share Repurchases [Line Items] | ' |
| Percentage of outstanding common shares available for repurchase | 10.00% |
| Outstanding common shares | 1,800,000 |
Transactions_in_Share_Repurcha
| Transactions in Share Repurchases (Detail) (USD $) | 9 Months Ended |
| Sep. 30, 2013 | |
| Share Repurchases [Line Items] | ' |
| Shares repurchased | 117,500 |
| Weighted average price per share | $17.89 |
Financial_Highlights_Detail
| Financial Highlights (Detail) (USD $) | 3 Months Ended | 9 Months Ended | ||
| Sep. 30, 2013 | Sep. 30, 2013 | |||
| Net Asset Value: | ' | ' | ||
| Net asset value per share-beginning of period | $21.11 | $22.72 | ||
| Net investment income (loss) | ($0.09) | ($0.26) | ||
| Net realized and unrealized gain (loss) | ($0.08) | ($0.60) | ||
| Distributions | ($0.47) | ($1.39) | ||
| Discount from shares repurchased and retired | $0.01 | $0.01 | ||
| Net asset value per share-end of period | $20.48 | $20.48 | ||
| Market Value: | ' | ' | ||
| Market value per share-beginning of period | $19.87 | $21.22 | ||
| Market value per share-end of period | $17.23 | $17.23 | ||
| Ratios to Average Net Assets: | ' | ' | ||
| Net investment income (loss) | -1.62% | [1] | -1.62% | [1] |
| Expenses | 1.73% | [1] | 1.74% | [1] |
| Total Returns: | ' | ' | ||
| Based on Net Asset Value | -0.80% | [2] | -3.77% | [2] |
| Based on Market Value | -10.99% | [2] | -12.80% | [2] |
| [1] | Annualized. | |||
| [2] | Total Return Based on Net Asset Value is the combination of changes in net asset value per share and the assumed reinvestment of distributions, if any, at net asset value per share on the distribution payment date. The last distribution declared in the period, which is typically paid on the first business day of the following month, is assumed to be reinvested at the net asset value per share at the end of the period. Total returns are not annualized. Total Return Based on Market Value is the combination of changes in the market price per share and the assumed reinvestment of distributions, if any, at the ending market price per share on the distribution payment date. The last distribution declared in the period, which is typically paid on the first business day of the following month, is assumed to be reinvested at the ending market price per share at the end of the period. Total returns are not annualized. | |||