v3.26.1
Fair Value of ETC - Summary of changes in quantity of ETC and the respective fair value (Detail)
$ in Thousands
 3 Months Ended 6 Months Ended
Jun. 30, 2026
USD ($)
ETC
Jun. 30, 2025
USD ($)
ETC
Jun. 30, 2026
USD ($)
ETC
Jun. 30, 2025
USD ($)
ETC
Fair Value Disclosures [Abstract]        
Investment Owned, Balance | ETC     10,985,516.92607291 11,263,626.2550315
ETC contributed | ETC     0 0
ETC distributed for Sponsor's Fee, related party | ETC     (135,354.20377371) (138,780.8305803)
Net change in unrealized appreciation/depreciation on investment in ETC | ETC     0 0
Net realized gain on investment in ETC | ETC     0 0
Investment Owned, Balance | ETC 10,850,162.7222992 11,124,845.4244512 10,850,162.7222992 11,124,845.4244512
Investment Owned, Fair Value | $     $ 126,004 $ 283,055
ETC contributed | $     0 0
ETC distributed for Sponsor's Fee, related party | $     (1,216) (2,690)
Net change in unrealized appreciation/depreciation on investment in ETC | $ $ (13,606) $ (1,424) (49,682) (95,443)
Net realized gain on investment in ETC | $ 44 653 194 1,642
Investment Owned, Fair Value | $ $ 75,300 $ 186,564 $ 75,300 $ 186,564