Note 2 - Significant Accounting Policies - Activity in Gold Bullion (Details)	3 Months Ended			6 Months Ended			12 Months Ended
	Jun. 30, 2017 USD ($) oz		Jun. 30, 2016 USD ($) oz	Jun. 30, 2017 USD ($) oz		Jun. 30, 2016 USD ($) oz	Dec. 31, 2016 USD ($) oz
Beginning balance (Ounce) | oz	6,425,460		5,990,515	6,308,062		4,905,568	4,905,568
Gold bullion contributed (Ounce) | oz	450,189		820,637	805,861		2,180,850
Gold bullion distributed (Ounce) | oz	(108,710)		(114,276)	(343,077)		(386,328)
Gold bullion sold to pay expenses (Ounce) | oz	(4,047)		(3,912)	(7,954)		(7,126)
Ending balance (Ounce) | oz	6,762,892		6,692,964	6,762,892		6,692,964	6,308,062
Beginning balance, average cost	$ 7,847,423,443		$ 7,174,407,233	$ 7,706,923,343		$ 5,910,175,908	$ 5,910,175,908
Gold bullion contributed, average cost	568,086,499		1,058,872,811	999,543,283		2,652,702,811
Gold bullion distributed, average cost	(132,886,400)		(137,359,506)	(419,071,822)		(463,104,522)
Gold bullion sold to pay expenses, average cost	(4,946,225)		(4,697,404)	(9,717,487)		(8,551,063)
Ending balance, average cost	8,277,677,317		8,091,223,134	8,277,677,317		8,091,223,134	7,706,923,343
Beginning balance, fair value	7,998,734,500		7,410,267,384	7,311,674,849	[1]	5,210,940,144	5,210,940,144
Gold bullion contributed, fair value	568,086,499		1,058,872,811	999,543,283		2,652,702,811
Gold bullion distributed, fair value	(135,318,870)		(139,691,971)	(423,616,445)		(472,601,825)
Gold bullion sold to pay expenses, fair value	(5,082,699)		(4,844,359)	(9,760,059)		(8,540,156)
Net realized gain (loss), fair value	2,568,944		2,479,420	4,587,195		9,486,396	25,068,804
Net change in unrealized appreciation/depreciation, fair value	(27,785,695)		512,648,845	518,773,856		1,447,744,760	303,987,270
Ending balance, fair value	8,401,202,679	[1]	8,839,732,130	8,401,202,679	[1]	8,839,732,130	7,311,674,849	[1]
Gold bullion distributed, realized gain (loss)	2,432,470		2,332,465	4,544,623		9,497,303
Gold bullion sold to pay expenses, realized gain (loss)	136,474		146,955	42,572		(10,907)
Ending balance, realized gain (loss)	$ 2,568,944		$ 2,479,420	$ 4,587,195		$ 9,486,396	$ 25,068,804

[1] Cost of investment in gold bullion: $8,277,677,317 and $7,706,923,343, respectively.