v3.26.3
State Street Blackstone Senior Loan ETF Average Annual Total Returns
 12 Months Ended 46 Months Ended 51 Months Ended 59 Months Ended 60 Months Ended 81 Months Ended 117 Months Ended 120 Months Ended
Dec. 31, 2025
Dec. 31, 2025
Dec. 31, 2025
Dec. 31, 2025
Dec. 31, 2025
Dec. 31, 2025
Dec. 31, 2025
Dec. 31, 2025
Markit iBoxx USD Liquid Leveraged Loan Index (reflects no deduction for fees, expenses or taxes)[Member]                
Prospectus [Line Items]                
Average Annual Return, Percent 5.38%       5.22%     4.61%
Morningstar LSTA US Leveraged Loan 100 Index (reflects no deduction for fees, expenses or taxes)[Member]                
Prospectus [Line Items]                
Average Annual Return, Percent [1] 7.24%       6.29%     5.80%
Bloomberg U.S. Aggregate Bond Index (reflects no deduction for fees, expenses or taxes)[Member]                
Prospectus [Line Items]                
Average Annual Return, Percent 7.30% 1.01% (0.12%) (0.17%) (0.36%) 1.67% 1.72% 2.01%
State Street Blackstone Senior Loan ETF                
Prospectus [Line Items]                
Average Annual Return, Percent 6.65%       5.12%     4.76%
State Street Blackstone Senior Loan ETF | After Taxes on Distributions                
Prospectus [Line Items]                
Average Annual Return, Percent 3.38%       2.21%     2.30%
State Street Blackstone Senior Loan ETF | After Taxes on Distributions and Sales                
Prospectus [Line Items]                
Average Annual Return, Percent 3.87%       2.62%     2.55%
[1] As of January 15, 2026 the Morningstar LSTA US Leveraged Loan Index became the Sub-Adviser's primary comparison benchmark.