Schedules of Investments (Unaudited) - Investments (Details)	Mar. 31, 2017 USD ($) oz	Dec. 31, 2016 USD ($) oz	Mar. 31, 2016 USD ($) oz	Dec. 31, 2015 USD ($) oz
Silver bullion (Ounce) | oz	330,326,197	341,348,242	332,578,508	317,934,907
Investment in silver bullion, cost	$ 6,097,115,732	$ 6,305,715,839	$ 6,159,729,408	$ 5,979,251,955
Silver bullion fair value	5,965,691,104	5,543,495,441
Less Liabilities	(2,473,895)	(2,364,798)
Net Assets	$ 5,963,217,209	$ 5,541,130,643		$ 4,391,943,604