v3.25.4
Shareholder Report, Average Annual Return (Details)
 12 Months Ended 60 Months Ended 120 Months Ended
Dec. 31, 2025
Dec. 31, 2025
Dec. 31, 2025
C000099785      
Average Annual Return [Line Items]      
Line Graph and Table Measure Name Class A    
Average Annual Return, Percent (6.25%) 2.74% 4.36%
C000099787      
Average Annual Return [Line Items]      
Line Graph and Table Measure Name Class C    
Average Annual Return, Percent (2.21%) 3.22% 4.24%
C000099788      
Average Annual Return [Line Items]      
Line Graph and Table Measure Name Class R    
C000148175      
Average Annual Return [Line Items]      
Line Graph and Table Measure Name Class R6    
C000099789      
Average Annual Return [Line Items]      
Line Graph and Table Measure Name Class S    
C000099790      
Average Annual Return [Line Items]      
Line Graph and Table Measure Name Institutional Class    
Without Sales Load [Member] | C000099785      
Average Annual Return [Line Items]      
Average Annual Return, Percent (0.53%) 3.97% 4.98%
Without Sales Load [Member] | C000099787      
Average Annual Return [Line Items]      
Average Annual Return, Percent (1.23%) 3.22% 4.24%
Without Sales Load [Member] | C000099788      
Average Annual Return [Line Items]      
Average Annual Return, Percent (0.86%) 3.65% 4.65%
Without Sales Load [Member] | C000148175      
Average Annual Return [Line Items]      
Average Annual Return, Percent (0.08%) 4.44% 5.45%
Without Sales Load [Member] | C000099789      
Average Annual Return [Line Items]      
Average Annual Return, Percent (0.28%) 4.21% 5.23%
Without Sales Load [Member] | C000099790      
Average Annual Return [Line Items]      
Average Annual Return, Percent (0.13%) 4.35% 5.35%
DWS Index: S&P 500® Index      
Average Annual Return [Line Items]      
Average Annual Return, Percent 17.88% 14.42% 14.82%
DWS Index: S&P 500® Index      
Average Annual Return [Line Items]      
Average Annual Return, Percent 17.88% 14.42% 14.82%
DWS Index: S&P 500® Index      
Average Annual Return [Line Items]      
Average Annual Return, Percent 17.88% 14.42% 14.82%
DWS Index: S&P 500® Index      
Average Annual Return [Line Items]      
Average Annual Return, Percent 17.88% 14.42% 14.82%
DWS Index: S&P 500® Index      
Average Annual Return [Line Items]      
Average Annual Return, Percent 17.88% 14.42% 14.82%
DWS Index: S&P 500® Index      
Average Annual Return [Line Items]      
Average Annual Return, Percent 17.88% 14.42% 14.82%
DWS Index: FTSE NAREIT All Equity REITs Index      
Average Annual Return [Line Items]      
Average Annual Return, Percent 2.27% 4.85% 5.77%
DWS Index: FTSE NAREIT All Equity REITs Index      
Average Annual Return [Line Items]      
Average Annual Return, Percent 2.27% 4.85% 5.77%
DWS Index: FTSE NAREIT All Equity REITs Index      
Average Annual Return [Line Items]      
Average Annual Return, Percent 2.27% 4.85% 5.77%
DWS Index: FTSE NAREIT All Equity REITs Index      
Average Annual Return [Line Items]      
Average Annual Return, Percent 2.27% 4.85% 5.77%
DWS Index: FTSE NAREIT All Equity REITs Index      
Average Annual Return [Line Items]      
Average Annual Return, Percent 2.27% 4.85% 5.77%
DWS Index: FTSE NAREIT All Equity REITs Index      
Average Annual Return [Line Items]      
Average Annual Return, Percent 2.27% 4.85% 5.77%