v3.26.1
Expense Example - MainGate MLP Fund
Mar. 31, 2026
USD ($)
MainGate MLP Fund Class A  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year $ 738
Expense Example, with Redemption, 3 Years 1,080
Expense Example, with Redemption, 5 Years 1,445
Expense Example, with Redemption, 10 Years 2,468 [1]
MainGate MLP Fund Class C  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year 348
Expense Example, with Redemption, 3 Years 764
Expense Example, with Redemption, 5 Years 1,306
Expense Example, with Redemption, 10 Years 2,786 [1]
MainGate MLP Fund Class I  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year 148
Expense Example, with Redemption, 3 Years 459
Expense Example, with Redemption, 5 Years 792
Expense Example, with Redemption, 10 Years $ 1,735 [1]
[1] Class C shares automatically convert into Class A shares eight years after the purchase date. The 10-Year Expense Examples for Class C shares do not reflect the conversion to Class A shares after eight years.