Statements of Cash Flows (Unaudited) - USD ($)	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Cash flows from operating activities:
Net Income (Loss)	$ (30,727,823)	$ 41,965,414
Adjustments to reconcile net income (loss) to net cash provided by (used for) operating activities:
Cost of securities purchased	(2,337,437,564)	(3,188,207,541)
Proceeds from securities sold and matured	2,715,949,582	3,193,397,863
Net sales (purchases) of affiliated investments	(39,228,727)
Net accretion of discount on United States Treasury Obligations	(1,473,049)	(209,177)
Net realized (gain) loss on United States Treasury Obligations	880	(4,293)
Net change in unrealized (gain) loss on United States Treasury Obligations and Currency Futures Contracts	(53,306)	14,027,827
Cash transfer to Commodity Broker to satisfy variation margin requirements (Note 4)		55,249,567
Cash received (paid) to Commodity Broker to satisfy open variation margin, net (Note 4)		(49,728,664)
Change in operating receivables and liabilities:
Dividends from affiliates	(11,158)
Variation margin	5,164,582	(5,251,321)
Management fee	(254,293)	14,707
Brokerage commissions and fees	880	(401)
Net cash provided by (used for) operating activities	311,930,004	61,253,981
Cash flows from financing activities:
Proceeds from purchases of Shares	368,777,500	1,565,254,163
Redemption of Shares	(731,595,884)	(1,573,960,328)
Net cash provided by (used for) financing activities	(362,818,384)	(8,706,165)
Net change in cash	(50,888,380)	52,547,816
Cash at beginning of period	51,943,740	18,108,522
Cash at end of period	1,055,360	70,656,338
Supplemental disclosure of cash flow information
Cash paid for interest	$ 10,970	$ 19,776