Shareholder Fees - THE GABELLI UTILITIES FUND	Apr. 30, 2025 USD ($)
THE GABELLI UTILITIES FUND CLASS AAA
Prospectus [Line Items]
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price)	0.00%
Maximum Deferred Sales Charge (as a percentage)	0.00%
Maximum Sales Charge on Reinvested Dividends and Distributions (as a percentage)	0.00%
Redemption Fee (as a percentage of Amount Redeemed)	(2.00%)
Exchange Fee	$ 0
THE GABELLI UTILITIES FUND CLASS A
Prospectus [Line Items]
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price)	5.75%
Maximum Deferred Sales Charge (as a percentage)	0.00%
Maximum Sales Charge on Reinvested Dividends and Distributions (as a percentage)	0.00%
Redemption Fee (as a percentage of Amount Redeemed)	(2.00%)
Exchange Fee	$ 0
THE GABELLI UTILITIES FUND CLASS C
Prospectus [Line Items]
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price)	0.00%
Maximum Deferred Sales Charge (as a percentage)	1.00%
Maximum Sales Charge on Reinvested Dividends and Distributions (as a percentage)	0.00%
Redemption Fee (as a percentage of Amount Redeemed)	(2.00%)
Exchange Fee	$ 0
THE GABELLI UTILITIES FUND CLASS I
Prospectus [Line Items]
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price)	0.00%
Maximum Deferred Sales Charge (as a percentage)	0.00%
Maximum Sales Charge on Reinvested Dividends and Distributions (as a percentage)	0.00%
Redemption Fee (as a percentage of Amount Redeemed)	(2.00%)
Exchange Fee	$ 0

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