v3.25.1
Average Annual Total Returns
 12 Months Ended 60 Months Ended 75 Months Ended 120 Months Ended
Apr. 30, 2025
Dec. 31, 2024
Dec. 31, 2024
Dec. 31, 2024
Dec. 31, 2024
M S C I A C World Communication Services Index [Member]          
Prospectus [Line Items]          
Average Annual Return, Percent   31.95% 10.14%   7.53%
M S C I A C World Index [Member]          
Prospectus [Line Items]          
Average Annual Return, Percent   18.02% 10.58%   9.79%
Lipper Global Large Cap Growth Fund Classification [Member]          
Prospectus [Line Items]          
Average Annual Return, Percent   17.54% 9.58%   10.00%
M S C I E A F E Small Cap Index [Member]          
Prospectus [Line Items]          
Average Annual Return, Percent   2.32% 2.74%   5.95%
M S C I World Index [Member]          
Prospectus [Line Items]          
Average Annual Return, Percent   19.19% 11.70%   10.52%
GABELLI GLOBAL CONTENT & CONNECTIVITY FUND CLASS AAA          
Prospectus [Line Items]          
Average Annual Return, Percent   22.35% 5.61%   4.27%
GABELLI GLOBAL CONTENT & CONNECTIVITY FUND CLASS AAA | After Taxes on Distributions          
Prospectus [Line Items]          
Average Annual Return, Percent   20.57% 4.64%   3.03%
GABELLI GLOBAL CONTENT & CONNECTIVITY FUND CLASS AAA | After Taxes on Distributions and Sales          
Prospectus [Line Items]          
Average Annual Return, Percent   14.18% 4.22%   3.14%
GABELLI GLOBAL CONTENT & CONNECTIVITY FUND CLASS A          
Prospectus [Line Items]          
Average Annual Return, Percent   15.24% 4.36%   3.64%
GABELLI GLOBAL CONTENT & CONNECTIVITY FUND CLASS I          
Prospectus [Line Items]          
Average Annual Return, Percent   22.30% 5.61%   4.55%
The Gabelli Global Growth Fund CLASS AAA          
Prospectus [Line Items]          
Average Annual Return, Percent   29.71% 12.34%   11.36%
The Gabelli Global Growth Fund CLASS AAA | After Taxes on Distributions          
Prospectus [Line Items]          
Average Annual Return, Percent   29.02% 11.85%   10.27%
The Gabelli Global Growth Fund CLASS AAA | After Taxes on Distributions and Sales          
Prospectus [Line Items]          
Average Annual Return, Percent   18.10% 9.83%   9.03%
The Gabelli Global Growth Fund CLASS A          
Prospectus [Line Items]          
Average Annual Return, Percent   22.25% 11.01%   10.70%
The Gabelli Global Growth Fund CLASS I          
Prospectus [Line Items]          
Average Annual Return, Percent   29.71% 12.34%   11.66%
GABELLI INTERNATIONAL SMALL CAP FUND CLASS AAA          
Prospectus [Line Items]          
Average Annual Return, Percent   6.04% 1.57%   1.79%
GABELLI INTERNATIONAL SMALL CAP FUND CLASS AAA | After Taxes on Distributions          
Prospectus [Line Items]          
Average Annual Return, Percent   5.99% 1.73%   0.07%
GABELLI INTERNATIONAL SMALL CAP FUND CLASS AAA | After Taxes on Distributions and Sales          
Prospectus [Line Items]          
Average Annual Return, Percent   3.32% 1.05%   1.46%
GABELLI INTERNATIONAL SMALL CAP FUND CLASS A          
Prospectus [Line Items]          
Average Annual Return, Percent   11.45% 2.74%   0.96%
GABELLI INTERNATIONAL SMALL CAP FUND CLASS I          
Prospectus [Line Items]          
Average Annual Return, Percent   6.11% 1.60%   2.00%
The Gabelli Global Rising Income and Dividend Fund CLASS AAA          
Prospectus [Line Items]          
Average Annual Return, Percent   2.07% 5.10%   4.92%
The Gabelli Global Rising Income and Dividend Fund CLASS AAA | After Taxes on Distributions          
Prospectus [Line Items]          
Average Annual Return, Percent   1.44% 4.65%   4.57%
The Gabelli Global Rising Income and Dividend Fund CLASS AAA | After Taxes on Distributions and Sales          
Prospectus [Line Items]          
Average Annual Return, Percent   1.84% 4.05%   3.95%
The Gabelli Global Rising Income and Dividend Fund CLASS A          
Prospectus [Line Items]          
Average Annual Return, Percent   3.81% 3.86%   4.28%
The Gabelli Global Rising Income and Dividend Fund CLASS I          
Prospectus [Line Items]          
Average Annual Return, Percent   2.03% 5.10%   5.16%
Gabelli Global Mini Mites Fund CLASS AAA          
Prospectus [Line Items]          
Average Annual Return, Percent   10.88% 12.30% 9.05%  
Performance Inception Date Oct. 01, 2018        
Gabelli Global Mini Mites Fund CLASS AAA | After Taxes on Distributions          
Prospectus [Line Items]          
Average Annual Return, Percent   8.57% 9.79% 6.86%  
Gabelli Global Mini Mites Fund CLASS AAA | After Taxes on Distributions and Sales          
Prospectus [Line Items]          
Average Annual Return, Percent   7.88% 9.07% 6.50%  
Gabelli Global Mini Mites Fund CLASS A          
Prospectus [Line Items]          
Average Annual Return, Percent   4.60% 10.98% 8.01%  
Performance Inception Date Oct. 01, 2018        
Gabelli Global Mini Mites Fund CLASS I          
Prospectus [Line Items]          
Average Annual Return, Percent   10.88% 12.30% 9.09%  
Performance Inception Date Oct. 01, 2018        
Gabelli Global Mini Mites Fund CLASS I | S P Developed Small Cap Index [Member]          
Prospectus [Line Items]          
Average Annual Return, Percent   8.64% 6.60% 5.97%