v3.26.1
S000076879 [Member] Average Annual Total Returns
 12 Months Ended 40 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% 3.94% [1]
Bloomberg Municipal Short (1-5 Year) Index (reflects no deduction for fees, expenses, or taxes)    
Prospectus [Line Items]    
Average Annual Return, Percent 4.11% 3.09% [1]
AB Tax-Aware Short Duration Municipal ETF    
Prospectus [Line Items]    
Average Annual Return, Percent 4.19% 3.53% [1]
Performance Inception Date   Sep. 14, 2022
AB Tax-Aware Short Duration Municipal ETF | After Taxes on Distributions    
Prospectus [Line Items]    
Average Annual Return, Percent [2] 4.10% 3.39% [1]
Performance Inception Date [2]   Sep. 14, 2022
AB Tax-Aware Short Duration Municipal ETF | After Taxes on Distributions and Sales    
Prospectus [Line Items]    
Average Annual Return, Percent [2] 3.74% 3.33% [1]
Performance Inception Date [2]   Sep. 14, 2022
[1] Inception date is 9/14/22.
[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.