Schedule of Investments (Unaudited) - Futures Contracts		3 Months Ended	12 Months Ended
		Mar. 31, 2019 USD ($) Contract	Dec. 31, 2018 USD ($) Contract
Schedule of Investments [Line Items]
Currency Futures Contracts, Value		$ 372,782,626	$ 511,601,546
Futures [Member] | United States of America, Dollars [Member] | Long [Member]
Schedule of Investments [Line Items]
Currency Futures Contracts, Number of Contracts | Contract		3,868	5,164
Currency Futures Contracts, Expiration Date		Jun. 30, 2019	Mar. 31, 2019
Currency Futures Contracts, Notional Value		$ 374,596,460	$ 494,375,540
Currency Futures Contracts, Value	[1]	2,511,116	(4,534,517)
Currency Futures Contracts, Unrealized Appreciation (Depreciation)	[1]	$ 2,511,116	$ (4,534,517)

[1] Unrealized Appreciation (Depreciation) and Value are presented above, net by contract.