v3.26.1
S000027257 [Member] Average Annual Total Returns
 12 Months Ended 60 Months Ended 119 Months Ended 120 Months Ended 192 Months Ended
Dec. 31, 2025
Dec. 31, 2025
Dec. 31, 2025
Dec. 31, 2025
Dec. 31, 2025
MSCI USA IMI Extended Real Estate Index (reflects no deduction for fees, expenses or taxes)          
Prospectus [Line Items]          
Average Annual Return, Percent 4.88% 8.64%   8.88% 10.77%
MSCI US REIT Index (reflects no deduction for fees, expenses or taxes)          
Prospectus [Line Items]          
Average Annual Return, Percent 1.68% 5.35%   4.42% 7.62%
S&P 500 Index (reflects no deduction for fees, expenses or taxes)          
Prospectus [Line Items]          
Average Annual Return, Percent 17.88% 14.42%   14.82% 14.13%
Retail Shares          
Prospectus [Line Items]          
Average Annual Return, Percent 4.92% 5.38%   10.40% 12.84%
Performance Inception Date         Dec. 31, 2009
Retail Shares | After Taxes on Distributions          
Prospectus [Line Items]          
Average Annual Return, Percent 4.05% 4.57%   9.07% 11.89%
Performance Inception Date         Dec. 31, 2009
Retail Shares | After Taxes on Distributions and Sales          
Prospectus [Line Items]          
Average Annual Return, Percent 3.55% 4.06%   8.16% 10.86%
Performance Inception Date         Dec. 31, 2009
Institutional Shares          
Prospectus [Line Items]          
Average Annual Return, Percent 5.19% 5.65%   10.69% 13.13%
Performance Inception Date         Dec. 31, 2009
R6 Shares          
Prospectus [Line Items]          
Average Annual Return, Percent [1] 5.19% 5.65% 13.13% 10.69%  
Performance Inception Date [1]     Jan. 29, 2016    
[1] Performance for the R6 Shares prior to January 29, 2016 is based on the performance of the Institutional Shares.