v3.25.4
Average Annual Total Returns
 12 Months Ended 43 Months Ended 60 Months Ended 64 Months Ended 78 Months Ended 120 Months Ended
Oct. 31, 2025
Dec. 31, 2024
Dec. 31, 2024
Dec. 31, 2024
Dec. 31, 2024
Dec. 31, 2024
Dec. 31, 2024
BBH Select Large Cap ETF              
Prospectus [Line Items]              
Average Annual Return, Label [Optional Text] Return Before Taxes            
Average Annual Return, Percent   14.26%   10.62% 11.05%    
Performance Inception Date Sep. 09, 2019            
BBH Select Large Cap ETF | After Taxes on Distributions              
Prospectus [Line Items]              
Average Annual Return, Label [Optional Text] Return After Taxes on Distributions            
Average Annual Return, Percent   11.89%   9.69% 10.29%    
BBH Select Large Cap ETF | After Taxes on Distributions and Sales              
Prospectus [Line Items]              
Average Annual Return, Label [Optional Text] Return After Taxes on Distributions and Sale of Fund Shares            
Average Annual Return, Percent   10.08%   8.36% 8.84%    
BBH Select Mid Cap ETF              
Prospectus [Line Items]              
Average Annual Return, Label [Optional Text] Return Before Taxes            
Average Annual Return, Percent   (5.64%) 2.72%        
Performance Inception Date May 24, 2021            
BBH Select Mid Cap ETF | After Taxes on Distributions              
Prospectus [Line Items]              
Average Annual Return, Label [Optional Text] Return After Taxes on Distributions            
Average Annual Return, Percent   (5.64%) 2.69%        
BBH Select Mid Cap ETF | After Taxes on Distributions and Sales              
Prospectus [Line Items]              
Average Annual Return, Label [Optional Text] Return After Taxes on Distributions and Sale of Fund Shares            
Average Annual Return, Percent   (3.34%) 2.09%        
Class I Shares              
Prospectus [Line Items]              
Average Annual Return, Label [Optional Text] Return Before Taxes            
Average Annual Return, Percent   26.19%   3.72%     8.03%
Class I Shares | After Taxes on Distributions              
Prospectus [Line Items]              
Average Annual Return, Label [Optional Text] Return After Taxes on Distributions            
Average Annual Return, Percent   25.84%   2.94%     7.06%
Class I Shares | After Taxes on Distributions and Sales              
Prospectus [Line Items]              
Average Annual Return, Label [Optional Text] Return After Taxes on Distributions and Sale of Fund Shares            
Average Annual Return, Percent   16.03%   2.78%     6.29%
Class N Shares              
Prospectus [Line Items]              
Average Annual Return, Label [Optional Text] Return Before Taxes            
Average Annual Return, Percent   5.53%   3.94%     3.38%
Class N Shares | After Taxes on Distributions              
Prospectus [Line Items]              
Average Annual Return, Label [Optional Text] Return After Taxes on Distributions            
Average Annual Return, Percent   3.56%   2.47%     2.15%
Class N Shares | After Taxes on Distributions and Sales              
Prospectus [Line Items]              
Average Annual Return, Label [Optional Text] Return After Taxes on Distributions and Sale of Fund Shares            
Average Annual Return, Percent   3.48%   2.40%     2.06%
Class I Shares              
Prospectus [Line Items]              
Average Annual Return, Label [Optional Text] Return Before Taxes            
Average Annual Return, Percent   5.61%   4.00%     3.47%
CLASS N SHARES              
Prospectus [Line Items]              
Average Annual Return, Label [Optional Text] Return Before Taxes            
Average Annual Return, Percent 3.79% 7.85%   1.38%      
CLASS N SHARES | After Taxes on Distributions              
Prospectus [Line Items]              
Average Annual Return, Label [Optional Text] Return After Taxes on Distributions            
Average Annual Return, Percent 1.69% 5.54%   (0.55%)      
CLASS N SHARES | After Taxes on Distributions and Sales              
Prospectus [Line Items]              
Average Annual Return, Label [Optional Text] Return After Taxes on Distributions and Sale of Fund Shares            
Average Annual Return, Percent 2.02% 4.91%   0.23%      
CLASS I SHARES              
Prospectus [Line Items]              
Performance Inception Date Jun. 27, 2018            
Class N Shares              
Prospectus [Line Items]              
Average Annual Return, Label [Optional Text] Return Before Taxes            
Average Annual Return, Percent   5.11%   1.32%     2.65%
Class N Shares | After Taxes on Distributions              
Prospectus [Line Items]              
Average Annual Return, Label [Optional Text] Return After Taxes on Distributions            
Average Annual Return, Percent   5.02%   1.26%     2.49%
Class N Shares | After Taxes on Distributions and Sales              
Prospectus [Line Items]              
Average Annual Return, Label [Optional Text] Return After Taxes on Distributions and Sale of Fund Shares            
Average Annual Return, Percent   4.66%   1.55%     2.48%
Class I Shares              
Prospectus [Line Items]              
Average Annual Return, Label [Optional Text] Return Before Taxes            
Average Annual Return, Percent   5.44%   1.53%     2.84%
Institutional Shares              
Prospectus [Line Items]              
Average Annual Return, Percent   4.09%   3.06%     1.98%
S&P 500 Index (reflects no deduction of fees, expenses or taxes)              
Prospectus [Line Items]              
Average Annual Return, Label [Optional Text] S&P 500 Index (reflects no deduction of fees, expenses or taxes)            
Average Annual Return, Percent   17.88%   14.42% 15.88%    
S&P 500 Index (reflects no deduction for fees, expenses or taxes)              
Prospectus [Line Items]              
Average Annual Return, Label [Optional Text] S&P 500 Index (reflects no deduction for fees, expenses or taxes)            
Average Annual Return, Percent   17.88% 12.85%        
Russell Mid Cap Total Return Index (reflects no deduction for fees, expenses or taxes)              
Prospectus [Line Items]              
Average Annual Return, Label [Optional Text] Russell Midcap Total Return Index (reflects no deduction for fees, expenses or taxes)            
Average Annual Return, Percent   10.60% 6.48%        
MSCI-EAFE Index (reflects no deduction for fees, expenses or taxes)              
Prospectus [Line Items]              
Average Annual Return, Label [Optional Text] MSCI-EAFE Index (reflects no deduction for fees, expenses or taxes)            
Average Annual Return, Percent   31.22%   8.92%     8.18%
Bloomberg US Aggregate Index (reflects no deduction for fees, expenses or taxes)              
Prospectus [Line Items]              
Average Annual Return, Label [Optional Text] Bloomberg US Aggregate Index (reflects no deduction for fees, expenses or taxes)            
Average Annual Return, Percent   7.30%   (0.36%)   2.07% 2.01%
Bloomberg U.S. 1-3 Year Treasury Bond Index (reflects no deduction for fees, expenses or taxes)              
Prospectus [Line Items]              
Average Annual Return, Label [Optional Text] Bloomberg U.S. 1-3 Year Treasury Bond Index (reflects no deduction for fees, expenses or taxes)            
Average Annual Return, Percent   5.17%   1.75%     1.83%
Reference Benchmark (an unmanaged weighted index comprised as follows: 40% Bloomberg Short-Term Corporate Index; 40% Bloomberg US Aggregate ABS Index; and 20% Bloomberg US Treasury Bills Index)              
Prospectus [Line Items]              
Average Annual Return, Label [Optional Text] Reference Benchmark (an unmanaged weighted index comprised as follows: 40% Bloomberg Short-Term Corporate Index; 40% Bloomberg US Aggregate ABS Index; and 20% Bloomberg US Treasury Bills Index)            
Average Annual Return, Percent   5.16%   2.98%     2.60%
Bloomberg Municipal Bond 1-15 Year Blend Index (reflects no deduction of fees, expenses or taxes)              
Prospectus [Line Items]              
Average Annual Return, Label [Optional Text] Bloomberg Municipal Bond 1-15 Year Blend Index (reflects no deduction of fees, expenses or taxes)            
Average Annual Return, Percent   5.18%   1.16%     2.27%