Statements of Cash Flows - USD ($)		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Cash flows from operating activities:
Net Income (Loss)		$ 27,600,800	$ 60,141,212	$ 93,337,407
Adjustments to reconcile net income (loss) to net cash provided by (used for) operating activities:
Cost of securities purchased		(3,297,920,688)	(4,621,990,413)	(3,152,761,429)
Proceeds from securities sold and matured		3,531,890,948	4,514,389,568	2,838,996,146
Net sales (purchases) of affiliated investments		(3,786,312)
Net accretion of discount on United States Treasury Obligations		(2,271,490)	(336,658)	(272,157)
Net realized (gain) loss on United States Treasury Obligations		(3,553)	(2,884)	(7,437)
Net change in unrealized (gain) loss on United States Treasury Obligations and Currency Futures Contracts		59,876	10,497,926	(20,168,903)
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)			(46,172,954)
Change in operating receivables and liabilities:
Dividends from affiliates		(16,819)
Variation margin		8,004,212	(4,489,462)
Management fee		(195,719)	82,812	200,026
Brokerage commissions and fees		382	(1,246)	3,604
Net cash provided by (used for) operating activities		263,361,637	(32,632,532)	(240,672,743)
Cash flows from financing activities:
Proceeds from purchases of Shares		629,567,756	1,924,757,103	667,690,541
Redemption of Shares		(944,874,133)	(1,858,289,353)	(421,010,213)
Increase in payable for amount due to custodian, net		1,000
Net cash provided by (used for) financing activities		(315,305,377)	66,467,750	246,680,328
Net change in cash		(51,943,740)	33,835,218	6,007,585
Cash at beginning of period	[1],[2]	51,943,740	18,108,522	12,100,937
Cash at end of period	[1],[2]		51,943,740	18,108,522
Supplemental disclosure of cash flow information
Cash paid for interest		$ 14,496	$ 25,211	$ 88

[1] Cash at December 31, 2014 and prior reflects cash held by Predecessor Commodity Broker.

[2] Cash at December 31, 2016 and 2015 reflects cash held by the Custodian.