v3.26.1
S000082570 [Member] Average Annual Total Returns
 12 Months Ended 25 Months Ended
Dec. 31, 2025
Dec. 31, 2025
Bloomberg Municipal Bond Index (reflects no deduction for fees, expenses, or taxes)    
Prospectus [Line Items]    
Average Annual Return, Percent 4.25% 3.43% [1]
Bloomberg 20 Year (17-22) Municipal Index (reflects no deduction for fees, expenses, or taxes)    
Prospectus [Line Items]    
Average Annual Return, Percent 3.12% 3.21% [1]
AB Tax-Aware Long Municipal ETF    
Prospectus [Line Items]    
Average Annual Return, Percent 3.58% 3.98% [1]
Performance Inception Date   Dec. 13, 2023
AB Tax-Aware Long Municipal ETF | After Taxes on Distributions    
Prospectus [Line Items]    
Average Annual Return, Percent [2] 3.49% 3.88% [1]
Performance Inception Date [2]   Dec. 13, 2023
AB Tax-Aware Long Municipal ETF | After Taxes on Distributions and Sales    
Prospectus [Line Items]    
Average Annual Return, Percent [2] 3.74% 3.90% [1]
Performance Inception Date [2]   Dec. 13, 2023
[1]
Inception date is 12/13/23.
[2] After-tax returns: – Are an estimate, which is based on the highest historical individual federal marginal income tax rates, and do not reflect the impact of state and local taxes; actual after-tax returns depend on an individual investor’s tax situation and are likely to differ from those shown; and – Are not relevant to investors who hold Fund shares through tax-deferred arrangements such as 401(k) plans or individual retirement accounts.