Derivative Instruments (Offsetting Derivative Assets) (Details) - USD ($)	6 Months Ended	12 Months Ended
Jun. 30, 2020	Dec. 31, 2019
Offsetting Assets [Line Items]
Gross amounts of recognized assets	$ 2,159,122	$ 2,586,512
Gross amounts offset in the Statement of Financial Condition	(1,304,140)	(1,489,040)
Net amounts of assets presented in the Statement of Financial Condition	854,982	1,097,472
Financial Instruments
Collateral Received	(854,982)	(1,097,472)
Net Amount
Collateral disclosed as a percentage of net assets, maximum allowed	100.00%	100.00%
Counterparty C [Member]
Offsetting Assets [Line Items]
Net amounts of assets presented in the Statement of Financial Condition	$ 472,631	$ 375,182
Financial Instruments
Collateral Received	(472,631)	(375,182)
Net Amount
Counterparty I [Member]
Offsetting Assets [Line Items]
Net amounts of assets presented in the Statement of Financial Condition	144,560	312,688
Financial Instruments
Collateral Received	(144,560)	(312,688)
Net Amount
Counterparty J [Member]
Offsetting Assets [Line Items]
Net amounts of assets presented in the Statement of Financial Condition	237,791	409,602
Financial Instruments
Collateral Received	(237,791)	(409,602)
Net Amount
Futures Contracts [Member] \| Counterparty C [Member]
Offsetting Assets [Line Items]
Gross amounts of recognized assets	598,639	719,162
Gross amounts offset in the Statement of Financial Condition	(126,008)	(343,980)
Net amounts of assets presented in the Statement of Financial Condition	472,631	375,182
Futures Contracts [Member] \| Counterparty I [Member]
Offsetting Assets [Line Items]
Gross amounts of recognized assets	1,183,078	1,247,715
Gross amounts offset in the Statement of Financial Condition	(1,038,518)	(935,027)
Net amounts of assets presented in the Statement of Financial Condition	144,560	312,688
Futures Contracts [Member] \| Counterparty J [Member]
Offsetting Assets [Line Items]
Gross amounts of recognized assets	377,405	619,635
Gross amounts offset in the Statement of Financial Condition	(139,614)	(210,033)
Net amounts of assets presented in the Statement of Financial Condition	$ 237,791	$ 409,602

Collateral As A Percentage Of Net Assets, Maximum

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- Definition

Amount of obligation to return cash collateral under master netting arrangements offset against derivative assets.

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Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and elected not to be offset.

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Fair value of liability associated with financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset.

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Fair value, after effects of master netting arrangements, deduction of assets not subject to a master netting arrangement and elected not to be offset, of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, offset against an obligation to return collateral.

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Fair value of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, not subject to a master netting arrangement, deducted from derivative assets.

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