Statements of Cash Flows - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Cash flows from operating activities:
Net Income (Loss)	$ 13,468,833	$ 38,849,945	$ (61,705,741)
Adjustments to reconcile net income (loss) to net cash provided by (used for) operating activities:
Cost of securities purchased	(915,211,456)	(1,054,042,847)	(1,706,093,799)
Proceeds from securities sold and matured	1,206,589,525	1,112,621,356	2,096,851,670
Cost of affiliated investments purchased	(766,376,656)	(722,071,670)	(1,045,572,170)
Proceeds from affiliated investments sold	763,039,150	700,995,257	968,029,450
Net accretion of discount on United States Treasury Obligations	(5,528,827)	(7,771,473)	(4,793,315)
Net realized (gain) loss on United States Treasury Obligations and Affiliated Investments	(61,775)	26,350	7,094
Net change in unrealized (gain) loss on United States Treasury Obligations and Affiliated Investments	(125,069)	(174,316)	331,991
Change in operating assets and liabilities:
Variation margin- Currency Futures Contracts	(384,045)	(1,561,281)	(739,851)
Dividends from affiliates	30,303	(36,013)	(5,890)
Management fees	(170,581)	(36,684)	(171,711)
Brokerage commissions and fees	(653)	156	302
Net cash provided by (used for) operating activities	295,268,749	66,798,780	246,138,030
Cash flows from financing activities:
Distributions paid to Shareholders	(5,050,773)	(5,572,383)	(538,669)
Proceeds from purchases of Shares	201,428,538	406,980,619	392,781,258
Redemption of Shares	(485,847,145)	(462,961,642)	(638,919,288)
Increase (decrease) in payable for amount due to custodian		(539,669)	538,669
Net cash provided by (used for) financing activities	(289,469,380)	(62,093,075)	(246,138,030)
Net change in cash	5,799,369	4,705,705
Cash at beginning of period	4,705,705	0	0
Cash at end of period	10,505,074	4,705,705	0
Supplemental disclosure of cash flow information
Cash paid for interest	$ 10,911	$ 20,856	$ 9,086