v3.26.1
Related Party Transactions - Disbursements to Trustees (Detail) - USD ($)
12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Related Party Transaction [Line Items]    
Trustee Fees and Expenses $ 32,500 $ 30,000
Corporate Trustee [Member]    
Related Party Transaction [Line Items]    
Trustee Fees and Expenses 2,500 2,500
Corporate Trustee Transfer Agent Registrar Fees [Member]    
Related Party Transaction [Line Items]    
Trustee Fees and Expenses [1] 27,500 24,375
Individual Trustee Fees [Member]    
Related Party Transaction [Line Items]    
Trustee Fees and Expenses $ 2,500 $ 3,125
[1] These services are performed by the Corporate Trustee.