Statements of Assets and Liabilities (Parenthetical) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2019	Dec. 31, 2018
Investment in Bullion at cost	$ 338,876	$ 351,430
Common stock, shares authorized	Unlimited	Unlimited
Common stock, par value
Common stock, shares issued	5,500,000	5,700,000
Common stock, shares outstanding	5,500,000	5,700,000
Net asset values per Share	$ 63.88	$ 63.03
Gold [Member]
Investment in Bullion at cost	$ 193,543	$ 200,683
Silver [Member]
Investment in Bullion at cost	98,754	102,655
Platinum [Member]
Investment in Bullion at cost	21,965	22,888
Palladium [Member]
Investment in Bullion at cost	$ 24,614	$ 25,204

Face amount per share of no-par value common stock.

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