v3.25.2
Shareholder Report, Average Annual Return (Details)
 6 Months Ended 12 Months Ended 60 Months Ended 120 Months Ended
Jun. 30, 2025
Jun. 30, 2025
Jun. 30, 2025
Jun. 30, 2025
C000002893        
Average Annual Return [Line Items]        
Line Graph and Table Measure Name The Gabelli Growth Fund - Class AAA      
C000002895        
Average Annual Return [Line Items]        
Line Graph and Table Measure Name The Gabelli Growth Fund - Class C      
Average Annual Return, Percent 9.40% 16.22% 14.14% 14.60%
C000002896        
Average Annual Return [Line Items]        
Line Graph and Table Measure Name The Gabelli Growth Fund - Class I      
C000002892        
Average Annual Return [Line Items]        
Line Graph and Table Measure Name The Gabelli Growth Fund - Class A      
Average Annual Return, Percent 4.43% 11.30% 13.64% 14.78%
Without Sales Load [Member] | C000002893        
Average Annual Return [Line Items]        
Average Annual Return, Percent 10.80% 18.08% 15.00% 15.46%
Without Sales Load [Member] | C000002895        
Average Annual Return [Line Items]        
Average Annual Return, Percent 10.40% 17.22% 14.14% 14.60%
Without Sales Load [Member] | C000002896        
Average Annual Return [Line Items]        
Average Annual Return, Percent 10.94% 18.39% 15.28% 15.75%
Without Sales Load [Member] | C000002892        
Average Annual Return [Line Items]        
Average Annual Return, Percent 10.80% 18.09% 15.00% 15.46%
S&P 500 Index        
Average Annual Return [Line Items]        
Average Annual Return, Percent 6.20% 15.16% 16.64% 13.65%
S&P 500 Index        
Average Annual Return [Line Items]        
Average Annual Return, Percent 6.20% 15.16% 16.64% 13.65%
S&P 500 Index        
Average Annual Return [Line Items]        
Average Annual Return, Percent 6.20% 15.16% 16.64% 13.65%
S&P 500 Index        
Average Annual Return [Line Items]        
Average Annual Return, Percent 6.20% 15.16% 16.64% 13.65%
Russell 1000 Growth Index        
Average Annual Return [Line Items]        
Average Annual Return, Percent 6.09% 17.22% 18.15% 17.01%
Russell 1000 Growth Index        
Average Annual Return [Line Items]        
Average Annual Return, Percent 6.09% 17.22% 18.15% 17.01%
Russell 1000 Growth Index        
Average Annual Return [Line Items]        
Average Annual Return, Percent 6.09% 17.22% 18.15% 17.01%
Russell 1000 Growth Index        
Average Annual Return [Line Items]        
Average Annual Return, Percent 6.09% 17.22% 18.15% 17.01%