XML 29 R17.htm IDEA: XBRL DOCUMENT v3.8.0.1
Significant Accounting Policies (Categorization Of The Trust's Assets) (Details) - USD ($)
$ in Thousands
Sep. 30, 2017
Dec. 31, 2016
Fair Value, Inputs, Level 2 [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investment in platinum $ 505,210 $ 474,220