Schedules of Investments - Investments (Details)	Dec. 31, 2020 USD ($) oz	Dec. 31, 2019 USD ($) oz	Dec. 31, 2018 USD ($) oz	Dec. 31, 2017 USD ($) oz
Silver bullion (Ounce) \| oz	558,715,882	362,616,711	317,233,610	320,629,662
Investment in silver bullion, cost	$ 10,472,474,303	$ 6,294,157,046	$ 5,641,558,156	$ 5,831,748,196
Silver bullion fair value	14,797,590,146	6,543,418,555
Less Liabilities	(5,797,426)	(2,659,990)
Net Assets	$ 14,791,792,720	$ 6,540,758,565	$ 4,904,036,623	$ 5,405,193,851

Value of the investment at close of period. For schedules of investments that are categorized, the value would be aggregated by category. For investment in and advances to affiliates, if operations of any controlled companies are different in character from those of the company, group such affiliates within divisions and by type of activities.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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