v3.25.2
Shareholder Report, Line Graph (Details) - USD ($)
 6 Months Ended
Jun. 30, 2025
Jun. 30, 2024
Jun. 30, 2023
Jun. 30, 2022
Jun. 30, 2021
Jun. 30, 2020
Jun. 30, 2019
Oct. 01, 2018
Jun. 30, 2018
Jun. 30, 2017
Jun. 30, 2016
Jun. 30, 2015
C000002867                        
Account Value [Line Items]                        
Line Graph and Table Measure Name The Gabelli Global Growth Fund - Class AAA                      
C000002869                        
Account Value [Line Items]                        
Line Graph and Table Measure Name The Gabelli Global Growth Fund - Class C                      
C000034309                        
Account Value [Line Items]                        
Line Graph and Table Measure Name The Gabelli Global Growth Fund - Class I                      
C000002866                        
Account Value [Line Items]                        
Line Graph and Table Measure Name The Gabelli Global Growth Fund - Class A                      
C000002875                        
Account Value [Line Items]                        
Line Graph and Table Measure Name The Gabelli Global Content & Connectivity Fund - Class AAA                      
C000002877                        
Account Value [Line Items]                        
Line Graph and Table Measure Name The Gabelli Global Content & Connectivity Fund - Class C                      
C000034311                        
Account Value [Line Items]                        
Line Graph and Table Measure Name The Gabelli Global Content & Connectivity Fund - Class I                      
C000002874                        
Account Value [Line Items]                        
Line Graph and Table Measure Name The Gabelli Global Content & Connectivity Fund - Class A                      
C000204772                        
Account Value [Line Items]                        
Line Graph and Table Measure Name The Gabelli Global Mini Mites Fund - Class A                      
C000204774                        
Account Value [Line Items]                        
Line Graph and Table Measure Name The Gabelli Global Mini Mites Fund - Class C                      
C000204771                        
Account Value [Line Items]                        
Line Graph and Table Measure Name The Gabelli Global Mini Mites Fund - Class I                      
C000204773                        
Account Value [Line Items]                        
Line Graph and Table Measure Name The Gabelli Global Mini Mites Fund - Class AAA                      
C000002865                        
Account Value [Line Items]                        
Line Graph and Table Measure Name The Gabelli Global Rising Income and Dividend Fund - Class AAA                      
C000002864                        
Account Value [Line Items]                        
Line Graph and Table Measure Name The Gabelli Global Rising Income and Dividend Fund - Class C                      
C000034308                        
Account Value [Line Items]                        
Line Graph and Table Measure Name The Gabelli Global Rising Income and Dividend Fund - Class I                      
C000002862                        
Account Value [Line Items]                        
Line Graph and Table Measure Name The Gabelli Global Rising Income and Dividend Fund - Class A                      
C000002873                        
Account Value [Line Items]                        
Line Graph and Table Measure Name The Gabelli International Small Cap Fund - Class AAA                      
C000002871                        
Account Value [Line Items]                        
Line Graph and Table Measure Name The Gabelli International Small Cap Fund - Class C                      
C000034310                        
Account Value [Line Items]                        
Line Graph and Table Measure Name The Gabelli International Small Cap Fund - Class I                      
C000002872                        
Account Value [Line Items]                        
Line Graph and Table Measure Name The Gabelli International Small Cap Fund - Class A                      
MSCI ACWI Index                        
Account Value [Line Items]                        
Account Value $ 27,252 $ 23,354 $ 19,475 $ 16,627 $ 19,646 $ 14,046 $ 13,685   $ 12,871 $ 11,563 $ 9,683 $ 10,000
MSCI ACWI Index                        
Account Value [Line Items]                        
Account Value 27,252 23,354 19,475 16,627 19,646 14,046 13,685   12,871 11,563 9,683 10,000
MSCI ACWI Index                        
Account Value [Line Items]                        
Account Value 27,252 23,354 19,475 16,627 19,646 14,046 13,685   12,871 11,563 9,683 10,000
MSCI ACWI Index                        
Account Value [Line Items]                        
Account Value 27,252 23,354 19,475 16,627 19,646 14,046 13,685   12,871 11,563 9,683 10,000
MSCI ACWI Index                        
Account Value [Line Items]                        
Account Value 27,252 23,354 19,475 16,627 19,646 14,046 13,685   12,871 11,563 9,683 10,000
MSCI ACWI Index                        
Account Value [Line Items]                        
Account Value 27,252 23,354 19,475 16,627 19,646 14,046 13,685   12,871 11,563 9,683 10,000
MSCI ACWI Index                        
Account Value [Line Items]                        
Account Value 27,252 23,354 19,475 16,627 19,646 14,046 13,685   12,871 11,563 9,683 10,000
MSCI ACWI Index                        
Account Value [Line Items]                        
Account Value 27,252 23,354 19,475 16,627 19,646 14,046 13,685   12,871 11,563 9,683 10,000
Russell 2000 Index                        
Account Value [Line Items]                        
Account Value 14,564 13,525 12,289 10,942 14,628 9,028 9,669 $ 10,000        
Russell 2000 Index                        
Account Value [Line Items]                        
Account Value 14,564 13,525 12,289 10,942 14,628 9,028 9,669 10,000        
Russell 2000 Index                        
Account Value [Line Items]                        
Account Value 14,564 13,525 12,289 10,942 14,628 9,028 9,669 10,000        
Russell 2000 Index                        
Account Value [Line Items]                        
Account Value 14,564 13,525 12,289 10,942 14,628 9,028 9,669 10,000        
MSCI World Index                        
Account Value [Line Items]                        
Account Value 28,989 24,828 20,562 17,260 20,056 14,359 13,887   12,986 11,626 9,781 10,000
MSCI World Index                        
Account Value [Line Items]                        
Account Value 28,989 24,828 20,562 17,260 20,056 14,359 13,887   12,986 11,626 9,781 10,000
MSCI World Index                        
Account Value [Line Items]                        
Account Value 28,989 24,828 20,562 17,260 20,056 14,359 13,887   12,986 11,626 9,781 10,000
MSCI World Index                        
Account Value [Line Items]                        
Account Value 28,989 24,828 20,562 17,260 20,056 14,359 13,887   12,986 11,626 9,781 10,000
MSCI EAFE Index                        
Account Value [Line Items]                        
Account Value 19,731 16,674 14,876 12,458 15,069 11,337 11,900   11,712 10,909 9,028 10,000
MSCI EAFE Index                        
Account Value [Line Items]                        
Account Value 19,731 16,674 14,876 12,458 15,069 11,337 11,900   11,712 10,909 9,028 10,000
MSCI EAFE Index                        
Account Value [Line Items]                        
Account Value 19,731 16,674 14,876 12,458 15,069 11,337 11,900   11,712 10,909 9,028 10,000
MSCI EAFE Index                        
Account Value [Line Items]                        
Account Value 19,731 16,674 14,876 12,458 15,069 11,337 11,900   11,712 10,909 9,028 10,000
Lipper Global Large-Cap Growth Fund Classification                        
Account Value [Line Items]                        
Account Value 27,394 24,036 19,929 16,674 22,265 16,182 14,563   13,240 11,625 9,747 10,000
Lipper Global Large-Cap Growth Fund Classification                        
Account Value [Line Items]                        
Account Value 27,394 24,036 19,929 16,674 22,265 16,182 14,563   13,240 11,625 9,747 10,000
Lipper Global Large-Cap Growth Fund Classification                        
Account Value [Line Items]                        
Account Value 27,394 24,036 19,929 16,674 22,265 16,182 14,563   13,240 11,625 9,747 10,000
Lipper Global Large-Cap Growth Fund Classification                        
Account Value [Line Items]                        
Account Value 27,394 24,036 19,929 16,674 22,265 16,182 14,563   13,240 11,625 9,747 10,000
MSCI AC World Communication Services Index                        
Account Value [Line Items]                        
Account Value 22,668 18,014 13,587 12,257 17,408 12,225 11,184   9,838 10,183 10,337 10,000
MSCI AC World Communication Services Index                        
Account Value [Line Items]                        
Account Value 22,668 18,014 13,587 12,257 17,408 12,225 11,184   9,838 10,183 10,337 10,000
MSCI AC World Communication Services Index                        
Account Value [Line Items]                        
Account Value 22,668 18,014 13,587 12,257 17,408 12,225 11,184   9,838 10,183 10,337 10,000
MSCI AC World Communication Services Index                        
Account Value [Line Items]                        
Account Value 22,668 18,014 13,587 12,257 17,408 12,225 11,184   9,838 10,183 10,337 10,000
MSCI World Micro Cap Index                        
Account Value [Line Items]                        
Account Value 14,116 11,724 11,157 10,864 14,527 8,790 9,044 10,000        
S&P Developed Small Cap Index                        
Account Value [Line Items]                        
Account Value 15,625 13,737 12,531 11,019 14,169 9,283 9,824 10,000        
MSCI World Micro Cap Index                        
Account Value [Line Items]                        
Account Value 14,116 11,724 11,157 10,864 14,527 8,790 9,044 10,000        
S&P Developed Small Cap Index                        
Account Value [Line Items]                        
Account Value 15,625 13,737 12,531 11,019 14,169 9,283 9,824 10,000        
MSCI World Micro Cap Index                        
Account Value [Line Items]                        
Account Value 14,116 11,724 11,157 10,864 14,527 8,790 9,044 10,000        
S&P Developed Small Cap Index                        
Account Value [Line Items]                        
Account Value 15,625 13,737 12,531 11,019 14,169 9,283 9,824 10,000        
MSCI World Micro Cap Index                        
Account Value [Line Items]                        
Account Value 14,116 11,724 11,157 10,864 14,527 8,790 9,044 10,000        
S&P Developed Small Cap Index                        
Account Value [Line Items]                        
Account Value 15,625 13,737 12,531 11,019 14,169 9,283 9,824 $ 10,000        
Lipper Global Large-Cap Growth Fund Classification                        
Account Value [Line Items]                        
Account Value 27,394 24,036 19,929 16,674 22,265 16,182 14,563   13,240 11,625 9,747 10,000
Lipper Global Large-Cap Growth Fund Classification                        
Account Value [Line Items]                        
Account Value 27,394 24,036 19,929 16,674 22,265 16,182 14,563   13,240 11,625 9,747 10,000
Lipper Global Large-Cap Growth Fund Classification                        
Account Value [Line Items]                        
Account Value 27,394 24,036 19,929 16,674 22,265 16,182 14,563   13,240 11,625 9,747 10,000
Lipper Global Large-Cap Growth Fund Classification                        
Account Value [Line Items]                        
Account Value 27,394 24,036 19,929 16,674 22,265 16,182 14,563   13,240 11,625 9,747 10,000
MSCI EAFE Small Cap Index                        
Account Value [Line Items]                        
Account Value 19,580 15,907 14,688 13,267 17,374 12,280 12,684   13,490 11,954 9,668 10,000
MSCI EAFE Small Cap Index                        
Account Value [Line Items]                        
Account Value 19,580 15,907 14,688 13,267 17,374 12,280 12,684   13,490 11,954 9,668 10,000
MSCI EAFE Small Cap Index                        
Account Value [Line Items]                        
Account Value 19,580 15,907 14,688 13,267 17,374 12,280 12,684   13,490 11,954 9,668 10,000
MSCI EAFE Small Cap Index                        
Account Value [Line Items]                        
Account Value $ 19,580 $ 15,907 $ 14,688 $ 13,267 $ 17,374 $ 12,280 $ 12,684   $ 13,490 $ 11,954 $ 9,668 $ 10,000