v3.26.1
Shareholder Report, Holdings (Details)
May 31, 2026
C000209569 [Member] | Kodiak Gas Services Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.70% [1]
C000209569 [Member] | NGL Energy Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.24% [1]
C000209569 [Member] | Williams Cos Inc The [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.38% [1]
C000209569 [Member] | ONEOK Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.51% [1]
C000209569 [Member] | Plains All American Pipeline L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.90% [1]
C000209569 [Member] | Targa Resources Corp [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.75% [1]
C000209569 [Member] | Enterprise Products Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.44% [1]
C000209569 [Member] | Western Midstream Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 7.56% [1]
C000209569 [Member] | Energy Transfer L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 7.40% [1]
C000209569 [Member] | MPLX L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 6.84% [1]
C000209569 [Member] | Natural Gas Pipeline Transportation [Member]  
Holdings [Line Items]  
Percent of Total Investments 3.80%
C000209569 [Member] | Terminalling And Storage [Member]  
Holdings [Line Items]  
Percent of Total Investments 0.00%
C000209569 [Member] | Production And Mining [Member]  
Holdings [Line Items]  
Percent of Total Investments 0.40%
C000209569 [Member] | Pipelines And Midstream Diversified [Member]  
Holdings [Line Items]  
Percent of Total Investments 0.60%
C000209569 [Member] | Other Energy Equipment [Member]  
Holdings [Line Items]  
Percent of Total Investments 27.40%
C000209569 [Member] | Gas Gathering and Processing Equipment [Member]  
Holdings [Line Items]  
Percent of Total Investments 21.70%
C000209569 [Member] | Petroleum Products [Member]  
Holdings [Line Items]  
Percent of Total Investments 17.10%
C000209569 [Member] | Diversified [Member]  
Holdings [Line Items]  
Percent of Total Investments 27.60%
C000209569 [Member] | Money Market Funds [Member]  
Holdings [Line Items]  
Percent of Total Investments 1.40%
C000209568 [Member] | Kodiak Gas Services Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.70% [2]
C000209568 [Member] | NGL Energy Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.24% [2]
C000209568 [Member] | Williams Cos Inc The [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.38% [2]
C000209568 [Member] | ONEOK Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.51% [2]
C000209568 [Member] | Plains All American Pipeline L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.90% [2]
C000209568 [Member] | Targa Resources Corp [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.75% [2]
C000209568 [Member] | Enterprise Products Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.44% [2]
C000209568 [Member] | Western Midstream Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 7.56% [2]
C000209568 [Member] | Energy Transfer L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 7.40% [2]
C000209568 [Member] | MPLX L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 6.84% [2]
C000209568 [Member] | Natural Gas Pipeline Transportation [Member]  
Holdings [Line Items]  
Percent of Total Investments 3.80%
C000209568 [Member] | Terminalling And Storage [Member]  
Holdings [Line Items]  
Percent of Total Investments 0.00%
C000209568 [Member] | Production And Mining [Member]  
Holdings [Line Items]  
Percent of Total Investments 0.40%
C000209568 [Member] | Pipelines And Midstream Diversified [Member]  
Holdings [Line Items]  
Percent of Total Investments 0.60%
C000209568 [Member] | Other Energy Equipment [Member]  
Holdings [Line Items]  
Percent of Total Investments 27.40%
C000209568 [Member] | Gas Gathering and Processing Equipment [Member]  
Holdings [Line Items]  
Percent of Total Investments 21.70%
C000209568 [Member] | Petroleum Products [Member]  
Holdings [Line Items]  
Percent of Total Investments 17.10%
C000209568 [Member] | Diversified [Member]  
Holdings [Line Items]  
Percent of Total Investments 27.60%
C000209568 [Member] | Money Market Funds [Member]  
Holdings [Line Items]  
Percent of Total Investments 1.40%
C000209567 [Member] | Kodiak Gas Services Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.70% [3]
C000209567 [Member] | NGL Energy Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.24% [3]
C000209567 [Member] | Williams Cos Inc The [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.38% [3]
C000209567 [Member] | ONEOK Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.51% [3]
C000209567 [Member] | Plains All American Pipeline L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.90% [3]
C000209567 [Member] | Targa Resources Corp [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.75% [3]
C000209567 [Member] | Enterprise Products Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.44% [3]
C000209567 [Member] | Western Midstream Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 7.56% [3]
C000209567 [Member] | Energy Transfer L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 7.40% [3]
C000209567 [Member] | MPLX L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 6.84% [3]
C000209567 [Member] | Natural Gas Pipeline Transportation [Member]  
Holdings [Line Items]  
Percent of Total Investments 3.80%
C000209567 [Member] | Terminalling And Storage [Member]  
Holdings [Line Items]  
Percent of Total Investments 0.00%
C000209567 [Member] | Production And Mining [Member]  
Holdings [Line Items]  
Percent of Total Investments 0.40%
C000209567 [Member] | Pipelines And Midstream Diversified [Member]  
Holdings [Line Items]  
Percent of Total Investments 0.60%
C000209567 [Member] | Other Energy Equipment [Member]  
Holdings [Line Items]  
Percent of Total Investments 27.40%
C000209567 [Member] | Gas Gathering and Processing Equipment [Member]  
Holdings [Line Items]  
Percent of Total Investments 21.70%
C000209567 [Member] | Petroleum Products [Member]  
Holdings [Line Items]  
Percent of Total Investments 17.10%
C000209567 [Member] | Diversified [Member]  
Holdings [Line Items]  
Percent of Total Investments 27.60%
C000209567 [Member] | Money Market Funds [Member]  
Holdings [Line Items]  
Percent of Total Investments 1.40%
C000209566 [Member] | Kodiak Gas Services Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.70% [4]
C000209566 [Member] | NGL Energy Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.24% [4]
C000209566 [Member] | Williams Cos Inc The [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.38% [4]
C000209566 [Member] | ONEOK Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.51% [4]
C000209566 [Member] | Plains All American Pipeline L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.90% [4]
C000209566 [Member] | Targa Resources Corp [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.75% [4]
C000209566 [Member] | Enterprise Products Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.44% [4]
C000209566 [Member] | Western Midstream Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 7.56% [4]
C000209566 [Member] | Energy Transfer L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 7.40% [4]
C000209566 [Member] | MPLX L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 6.84% [4]
C000209566 [Member] | Natural Gas Pipeline Transportation [Member]  
Holdings [Line Items]  
Percent of Total Investments 3.80%
C000209566 [Member] | Terminalling And Storage [Member]  
Holdings [Line Items]  
Percent of Total Investments 0.00%
C000209566 [Member] | Production And Mining [Member]  
Holdings [Line Items]  
Percent of Total Investments 0.40%
C000209566 [Member] | Pipelines And Midstream Diversified [Member]  
Holdings [Line Items]  
Percent of Total Investments 0.60%
C000209566 [Member] | Other Energy Equipment [Member]  
Holdings [Line Items]  
Percent of Total Investments 27.40%
C000209566 [Member] | Gas Gathering and Processing Equipment [Member]  
Holdings [Line Items]  
Percent of Total Investments 21.70%
C000209566 [Member] | Petroleum Products [Member]  
Holdings [Line Items]  
Percent of Total Investments 17.10%
C000209566 [Member] | Diversified [Member]  
Holdings [Line Items]  
Percent of Total Investments 27.60%
C000209566 [Member] | Money Market Funds [Member]  
Holdings [Line Items]  
Percent of Total Investments 1.40%
C000209565 [Member] | Kodiak Gas Services Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.70% [5]
C000209565 [Member] | NGL Energy Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.24% [5]
C000209565 [Member] | Williams Cos Inc The [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.38% [5]
C000209565 [Member] | ONEOK Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.51% [5]
C000209565 [Member] | Plains All American Pipeline L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.90% [5]
C000209565 [Member] | Targa Resources Corp [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.75% [5]
C000209565 [Member] | Enterprise Products Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.44% [5]
C000209565 [Member] | Western Midstream Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 7.56% [5]
C000209565 [Member] | Energy Transfer L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 7.40% [5]
C000209565 [Member] | MPLX L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 6.84% [5]
C000209565 [Member] | Natural Gas Pipeline Transportation [Member]  
Holdings [Line Items]  
Percent of Total Investments 3.80%
C000209565 [Member] | Terminalling And Storage [Member]  
Holdings [Line Items]  
Percent of Total Investments 0.00%
C000209565 [Member] | Production And Mining [Member]  
Holdings [Line Items]  
Percent of Total Investments 0.40%
C000209565 [Member] | Pipelines And Midstream Diversified [Member]  
Holdings [Line Items]  
Percent of Total Investments 0.60%
C000209565 [Member] | Other Energy Equipment [Member]  
Holdings [Line Items]  
Percent of Total Investments 27.40%
C000209565 [Member] | Gas Gathering and Processing Equipment [Member]  
Holdings [Line Items]  
Percent of Total Investments 21.70%
C000209565 [Member] | Petroleum Products [Member]  
Holdings [Line Items]  
Percent of Total Investments 17.10%
C000209565 [Member] | Diversified [Member]  
Holdings [Line Items]  
Percent of Total Investments 27.60%
C000209565 [Member] | Money Market Funds [Member]  
Holdings [Line Items]  
Percent of Total Investments 1.40%
C000209570 [Member] | Kodiak Gas Services Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.70% [6]
C000209570 [Member] | NGL Energy Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.24% [6]
C000209570 [Member] | Williams Cos Inc The [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.38% [6]
C000209570 [Member] | ONEOK Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.51% [6]
C000209570 [Member] | Plains All American Pipeline L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.90% [6]
C000209570 [Member] | Targa Resources Corp [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.75% [6]
C000209570 [Member] | Enterprise Products Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.44% [6]
C000209570 [Member] | Western Midstream Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 7.56% [6]
C000209570 [Member] | Energy Transfer L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 7.40% [6]
C000209570 [Member] | MPLX L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 6.84% [6]
C000209570 [Member] | Natural Gas Pipeline Transportation [Member]  
Holdings [Line Items]  
Percent of Total Investments 3.80%
C000209570 [Member] | Terminalling And Storage [Member]  
Holdings [Line Items]  
Percent of Total Investments 0.00%
C000209570 [Member] | Production And Mining [Member]  
Holdings [Line Items]  
Percent of Total Investments 0.40%
C000209570 [Member] | Pipelines And Midstream Diversified [Member]  
Holdings [Line Items]  
Percent of Total Investments 0.60%
C000209570 [Member] | Other Energy Equipment [Member]  
Holdings [Line Items]  
Percent of Total Investments 27.40%
C000209570 [Member] | Gas Gathering and Processing Equipment [Member]  
Holdings [Line Items]  
Percent of Total Investments 21.70%
C000209570 [Member] | Petroleum Products [Member]  
Holdings [Line Items]  
Percent of Total Investments 17.10%
C000209570 [Member] | Diversified [Member]  
Holdings [Line Items]  
Percent of Total Investments 27.60%
C000209570 [Member] | Money Market Funds [Member]  
Holdings [Line Items]  
Percent of Total Investments 1.40%
C000209574 [Member] | Williams Cos Inc The [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.52% [7]
C000209574 [Member] | ONEOK Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.81% [7]
C000209574 [Member] | Plains All American Pipeline L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 7.28% [7]
C000209574 [Member] | Targa Resources Corp [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 9.29% [7]
C000209574 [Member] | Enterprise Products Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 9.89% [7]
C000209574 [Member] | Western Midstream Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 10.42% [7]
C000209574 [Member] | Energy Transfer L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 11.92% [7]
C000209574 [Member] | MPLX L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 12.32% [7]
C000209574 [Member] | Hess Midstream L P Class A [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.28% [7]
C000209574 [Member] | Sunoco L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.10% [7]
C000209574 [Member] | Natural Gas Pipeline Transportation [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.80%
C000209574 [Member] | Other Energy Equipment [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 15.80%
C000209574 [Member] | Gas Gathering and Processing Equipment [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 26.10%
C000209574 [Member] | Petroleum Products [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 11.50%
C000209574 [Member] | Diversified [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 44.00%
C000209574 [Member] | Money Market Funds Plus Other Assets Less Liabilities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value (0.20%)
C000209575 [Member] | Williams Cos Inc The [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.52% [8]
C000209575 [Member] | ONEOK Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.81% [8]
C000209575 [Member] | Plains All American Pipeline L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 7.28% [8]
C000209575 [Member] | Targa Resources Corp [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 9.29% [8]
C000209575 [Member] | Enterprise Products Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 9.89% [8]
C000209575 [Member] | Western Midstream Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 10.42% [8]
C000209575 [Member] | Energy Transfer L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 11.92% [8]
C000209575 [Member] | MPLX L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 12.32% [8]
C000209575 [Member] | Hess Midstream L P Class A [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.28% [8]
C000209575 [Member] | Sunoco L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.10% [8]
C000209575 [Member] | Natural Gas Pipeline Transportation [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.80%
C000209575 [Member] | Other Energy Equipment [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 15.80%
C000209575 [Member] | Gas Gathering and Processing Equipment [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 26.10%
C000209575 [Member] | Petroleum Products [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 11.50%
C000209575 [Member] | Diversified [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 44.00%
C000209575 [Member] | Money Market Funds Plus Other Assets Less Liabilities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value (0.20%)
C000209576 [Member] | Williams Cos Inc The [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.52% [9]
C000209576 [Member] | ONEOK Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.81% [9]
C000209576 [Member] | Plains All American Pipeline L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 7.28% [9]
C000209576 [Member] | Targa Resources Corp [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 9.29% [9]
C000209576 [Member] | Enterprise Products Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 9.89% [9]
C000209576 [Member] | Western Midstream Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 10.42% [9]
C000209576 [Member] | Energy Transfer L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 11.92% [9]
C000209576 [Member] | MPLX L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 12.32% [9]
C000209576 [Member] | Hess Midstream L P Class A [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.28% [9]
C000209576 [Member] | Sunoco L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.10% [9]
C000209576 [Member] | Natural Gas Pipeline Transportation [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.80%
C000209576 [Member] | Other Energy Equipment [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 15.80%
C000209576 [Member] | Gas Gathering and Processing Equipment [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 26.10%
C000209576 [Member] | Petroleum Products [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 11.50%
C000209576 [Member] | Diversified [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 44.00%
C000209576 [Member] | Money Market Funds Plus Other Assets Less Liabilities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value (0.20%)
C000209573 [Member] | Williams Cos Inc The [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.52% [10]
C000209573 [Member] | ONEOK Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.81% [10]
C000209573 [Member] | Plains All American Pipeline L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 7.28% [10]
C000209573 [Member] | Targa Resources Corp [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 9.29% [10]
C000209573 [Member] | Enterprise Products Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 9.89% [10]
C000209573 [Member] | Western Midstream Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 10.42% [10]
C000209573 [Member] | Energy Transfer L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 11.92% [10]
C000209573 [Member] | MPLX L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 12.32% [10]
C000209573 [Member] | Hess Midstream L P Class A [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.28% [10]
C000209573 [Member] | Sunoco L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.10% [10]
C000209573 [Member] | Natural Gas Pipeline Transportation [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.80%
C000209573 [Member] | Other Energy Equipment [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 15.80%
C000209573 [Member] | Gas Gathering and Processing Equipment [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 26.10%
C000209573 [Member] | Petroleum Products [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 11.50%
C000209573 [Member] | Diversified [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 44.00%
C000209573 [Member] | Money Market Funds Plus Other Assets Less Liabilities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value (0.20%)
C000209571 [Member] | Williams Cos Inc The [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.52% [11]
C000209571 [Member] | ONEOK Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.81% [11]
C000209571 [Member] | Plains All American Pipeline L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 7.28% [11]
C000209571 [Member] | Targa Resources Corp [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 9.29% [11]
C000209571 [Member] | Enterprise Products Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 9.89% [11]
C000209571 [Member] | Western Midstream Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 10.42% [11]
C000209571 [Member] | Energy Transfer L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 11.92% [11]
C000209571 [Member] | MPLX L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 12.32% [11]
C000209571 [Member] | Hess Midstream L P Class A [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.28% [11]
C000209571 [Member] | Sunoco L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.10% [11]
C000209571 [Member] | Natural Gas Pipeline Transportation [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.80%
C000209571 [Member] | Other Energy Equipment [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 15.80%
C000209571 [Member] | Gas Gathering and Processing Equipment [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 26.10%
C000209571 [Member] | Petroleum Products [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 11.50%
C000209571 [Member] | Diversified [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 44.00%
C000209571 [Member] | Money Market Funds Plus Other Assets Less Liabilities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value (0.20%)
C000209572 [Member] | Williams Cos Inc The [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.52% [12]
C000209572 [Member] | ONEOK Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.81% [12]
C000209572 [Member] | Plains All American Pipeline L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 7.28% [12]
C000209572 [Member] | Targa Resources Corp [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 9.29% [12]
C000209572 [Member] | Enterprise Products Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 9.89% [12]
C000209572 [Member] | Western Midstream Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 10.42% [12]
C000209572 [Member] | Energy Transfer L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 11.92% [12]
C000209572 [Member] | MPLX L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 12.32% [12]
C000209572 [Member] | Hess Midstream L P Class A [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.28% [12]
C000209572 [Member] | Sunoco L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.10% [12]
C000209572 [Member] | Natural Gas Pipeline Transportation [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.80%
C000209572 [Member] | Other Energy Equipment [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 15.80%
C000209572 [Member] | Gas Gathering and Processing Equipment [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 26.10%
C000209572 [Member] | Petroleum Products [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 11.50%
C000209572 [Member] | Diversified [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 44.00%
C000209572 [Member] | Money Market Funds Plus Other Assets Less Liabilities [Member]  
Holdings [Line Items]  
Percent of Net Asset Value (0.20%)
C000209581 [Member] | Kodiak Gas Services Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.55% [13]
C000209581 [Member] | NGL Energy Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 4.77% [13]
C000209581 [Member] | Plains All American Pipeline L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 10.88% [13]
C000209581 [Member] | Enterprise Products Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 14.99% [13]
C000209581 [Member] | Western Midstream Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 15.29% [13]
C000209581 [Member] | Energy Transfer L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 14.91% [13]
C000209581 [Member] | MPLX L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 13.88% [13]
C000209581 [Member] | Sunoco L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 8.54% [13]
C000209581 [Member] | Antero Midstream Corp [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.61% [13]
C000209581 [Member] | USA Compression Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.66% [13]
C000209581 [Member] | Natural Gas Pipeline Transportation [Member]  
Holdings [Line Items]  
Percent of Total Investments 0.60%
C000209581 [Member] | Terminalling And Storage [Member]  
Holdings [Line Items]  
Percent of Total Investments 0.30%
C000209581 [Member] | Other Energy Equipment [Member]  
Holdings [Line Items]  
Percent of Total Investments 20.50%
C000209581 [Member] | Gas Gathering and Processing Equipment [Member]  
Holdings [Line Items]  
Percent of Total Investments 20.70%
C000209581 [Member] | Petroleum Products [Member]  
Holdings [Line Items]  
Percent of Total Investments 17.40%
C000209581 [Member] | Diversified [Member]  
Holdings [Line Items]  
Percent of Total Investments 39.40%
C000209581 [Member] | Money Market Funds [Member]  
Holdings [Line Items]  
Percent of Total Investments 1.10%
C000209580 [Member] | Kodiak Gas Services Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.55% [14]
C000209580 [Member] | NGL Energy Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 4.77% [14]
C000209580 [Member] | Plains All American Pipeline L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 10.88% [14]
C000209580 [Member] | Enterprise Products Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 14.99% [14]
C000209580 [Member] | Western Midstream Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 15.29% [14]
C000209580 [Member] | Energy Transfer L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 14.91% [14]
C000209580 [Member] | MPLX L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 13.88% [14]
C000209580 [Member] | Sunoco L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 8.54% [14]
C000209580 [Member] | Antero Midstream Corp [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.61% [14]
C000209580 [Member] | USA Compression Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.66% [14]
C000209580 [Member] | Natural Gas Pipeline Transportation [Member]  
Holdings [Line Items]  
Percent of Total Investments 0.60%
C000209580 [Member] | Terminalling And Storage [Member]  
Holdings [Line Items]  
Percent of Total Investments 0.30%
C000209580 [Member] | Other Energy Equipment [Member]  
Holdings [Line Items]  
Percent of Total Investments 20.50%
C000209580 [Member] | Gas Gathering and Processing Equipment [Member]  
Holdings [Line Items]  
Percent of Total Investments 20.70%
C000209580 [Member] | Petroleum Products [Member]  
Holdings [Line Items]  
Percent of Total Investments 17.40%
C000209580 [Member] | Diversified [Member]  
Holdings [Line Items]  
Percent of Total Investments 39.40%
C000209580 [Member] | Money Market Funds [Member]  
Holdings [Line Items]  
Percent of Total Investments 1.10%
C000209579 [Member] | Kodiak Gas Services Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.55% [15]
C000209579 [Member] | NGL Energy Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 4.77% [15]
C000209579 [Member] | Plains All American Pipeline L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 10.88% [15]
C000209579 [Member] | Enterprise Products Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 14.99% [15]
C000209579 [Member] | Western Midstream Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 15.29% [15]
C000209579 [Member] | Energy Transfer L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 14.91% [15]
C000209579 [Member] | MPLX L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 13.88% [15]
C000209579 [Member] | Sunoco L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 8.54% [15]
C000209579 [Member] | Antero Midstream Corp [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.61% [15]
C000209579 [Member] | USA Compression Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.66% [15]
C000209579 [Member] | Natural Gas Pipeline Transportation [Member]  
Holdings [Line Items]  
Percent of Total Investments 0.60%
C000209579 [Member] | Terminalling And Storage [Member]  
Holdings [Line Items]  
Percent of Total Investments 0.30%
C000209579 [Member] | Other Energy Equipment [Member]  
Holdings [Line Items]  
Percent of Total Investments 20.50%
C000209579 [Member] | Gas Gathering and Processing Equipment [Member]  
Holdings [Line Items]  
Percent of Total Investments 20.70%
C000209579 [Member] | Petroleum Products [Member]  
Holdings [Line Items]  
Percent of Total Investments 17.40%
C000209579 [Member] | Diversified [Member]  
Holdings [Line Items]  
Percent of Total Investments 39.40%
C000209579 [Member] | Money Market Funds [Member]  
Holdings [Line Items]  
Percent of Total Investments 1.10%
C000209578 [Member] | Kodiak Gas Services Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.55% [16]
C000209578 [Member] | NGL Energy Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 4.77% [16]
C000209578 [Member] | Plains All American Pipeline L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 10.88% [16]
C000209578 [Member] | Enterprise Products Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 14.99% [16]
C000209578 [Member] | Western Midstream Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 15.29% [16]
C000209578 [Member] | Energy Transfer L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 14.91% [16]
C000209578 [Member] | MPLX L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 13.88% [16]
C000209578 [Member] | Sunoco L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 8.54% [16]
C000209578 [Member] | Antero Midstream Corp [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.61% [16]
C000209578 [Member] | USA Compression Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.66% [16]
C000209578 [Member] | Natural Gas Pipeline Transportation [Member]  
Holdings [Line Items]  
Percent of Total Investments 0.60%
C000209578 [Member] | Terminalling And Storage [Member]  
Holdings [Line Items]  
Percent of Total Investments 0.30%
C000209578 [Member] | Other Energy Equipment [Member]  
Holdings [Line Items]  
Percent of Total Investments 20.50%
C000209578 [Member] | Gas Gathering and Processing Equipment [Member]  
Holdings [Line Items]  
Percent of Total Investments 20.70%
C000209578 [Member] | Petroleum Products [Member]  
Holdings [Line Items]  
Percent of Total Investments 17.40%
C000209578 [Member] | Diversified [Member]  
Holdings [Line Items]  
Percent of Total Investments 39.40%
C000209578 [Member] | Money Market Funds [Member]  
Holdings [Line Items]  
Percent of Total Investments 1.10%
C000209577 [Member] | Kodiak Gas Services Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.55% [17]
C000209577 [Member] | NGL Energy Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 4.77% [17]
C000209577 [Member] | Plains All American Pipeline L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 10.88% [17]
C000209577 [Member] | Enterprise Products Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 14.99% [17]
C000209577 [Member] | Western Midstream Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 15.29% [17]
C000209577 [Member] | Energy Transfer L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 14.91% [17]
C000209577 [Member] | MPLX L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 13.88% [17]
C000209577 [Member] | Sunoco L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 8.54% [17]
C000209577 [Member] | Antero Midstream Corp [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.61% [17]
C000209577 [Member] | USA Compression Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.66% [17]
C000209577 [Member] | Natural Gas Pipeline Transportation [Member]  
Holdings [Line Items]  
Percent of Total Investments 0.60%
C000209577 [Member] | Terminalling And Storage [Member]  
Holdings [Line Items]  
Percent of Total Investments 0.30%
C000209577 [Member] | Other Energy Equipment [Member]  
Holdings [Line Items]  
Percent of Total Investments 20.50%
C000209577 [Member] | Gas Gathering and Processing Equipment [Member]  
Holdings [Line Items]  
Percent of Total Investments 20.70%
C000209577 [Member] | Petroleum Products [Member]  
Holdings [Line Items]  
Percent of Total Investments 17.40%
C000209577 [Member] | Diversified [Member]  
Holdings [Line Items]  
Percent of Total Investments 39.40%
C000209577 [Member] | Money Market Funds [Member]  
Holdings [Line Items]  
Percent of Total Investments 1.10%
C000209582 [Member] | Kodiak Gas Services Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.55% [18]
C000209582 [Member] | NGL Energy Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 4.77% [18]
C000209582 [Member] | Plains All American Pipeline L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 10.88% [18]
C000209582 [Member] | Enterprise Products Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 14.99% [18]
C000209582 [Member] | Western Midstream Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 15.29% [18]
C000209582 [Member] | Energy Transfer L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 14.91% [18]
C000209582 [Member] | MPLX L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 13.88% [18]
C000209582 [Member] | Sunoco L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 8.54% [18]
C000209582 [Member] | Antero Midstream Corp [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.61% [18]
C000209582 [Member] | USA Compression Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.66% [18]
C000209582 [Member] | Natural Gas Pipeline Transportation [Member]  
Holdings [Line Items]  
Percent of Total Investments 0.60%
C000209582 [Member] | Terminalling And Storage [Member]  
Holdings [Line Items]  
Percent of Total Investments 0.30%
C000209582 [Member] | Other Energy Equipment [Member]  
Holdings [Line Items]  
Percent of Total Investments 20.50%
C000209582 [Member] | Gas Gathering and Processing Equipment [Member]  
Holdings [Line Items]  
Percent of Total Investments 20.70%
C000209582 [Member] | Petroleum Products [Member]  
Holdings [Line Items]  
Percent of Total Investments 17.40%
C000209582 [Member] | Diversified [Member]  
Holdings [Line Items]  
Percent of Total Investments 39.40%
C000209582 [Member] | Money Market Funds [Member]  
Holdings [Line Items]  
Percent of Total Investments 1.10%
C000209588 [Member] | Williams Cos Inc The [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.07% [19]
C000209588 [Member] | ONEOK Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.32% [19]
C000209588 [Member] | Plains All American Pipeline L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 10.31% [19]
C000209588 [Member] | Targa Resources Corp [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 13.33% [19]
C000209588 [Member] | Enterprise Products Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 13.97% [19]
C000209588 [Member] | Western Midstream Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 14.74% [19]
C000209588 [Member] | Energy Transfer L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 16.94% [19]
C000209588 [Member] | MPLX L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 17.34% [19]
C000209588 [Member] | Hess Midstream L P Class A [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 7.46% [19]
C000209588 [Member] | Sunoco L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 7.20% [19]
C000209588 [Member] | Natural Gas Pipeline Transportation [Member]  
Holdings [Line Items]  
Percent of Total Investments 2.70%
C000209588 [Member] | Other Energy Equipment [Member]  
Holdings [Line Items]  
Percent of Total Investments 15.70%
C000209588 [Member] | Gas Gathering and Processing Equipment [Member]  
Holdings [Line Items]  
Percent of Total Investments 26.10%
C000209588 [Member] | Petroleum Products [Member]  
Holdings [Line Items]  
Percent of Total Investments 11.50%
C000209588 [Member] | Diversified [Member]  
Holdings [Line Items]  
Percent of Total Investments 44.00%
C000209587 [Member] | Williams Cos Inc The [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.07% [20]
C000209587 [Member] | ONEOK Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.32% [20]
C000209587 [Member] | Plains All American Pipeline L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 10.31% [20]
C000209587 [Member] | Targa Resources Corp [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 13.33% [20]
C000209587 [Member] | Enterprise Products Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 13.97% [20]
C000209587 [Member] | Western Midstream Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 14.74% [20]
C000209587 [Member] | Energy Transfer L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 16.94% [20]
C000209587 [Member] | MPLX L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 17.34% [20]
C000209587 [Member] | Hess Midstream L P Class A [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 7.46% [20]
C000209587 [Member] | Sunoco L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 7.20% [20]
C000209587 [Member] | Natural Gas Pipeline Transportation [Member]  
Holdings [Line Items]  
Percent of Total Investments 2.70%
C000209587 [Member] | Other Energy Equipment [Member]  
Holdings [Line Items]  
Percent of Total Investments 15.70%
C000209587 [Member] | Gas Gathering and Processing Equipment [Member]  
Holdings [Line Items]  
Percent of Total Investments 26.10%
C000209587 [Member] | Petroleum Products [Member]  
Holdings [Line Items]  
Percent of Total Investments 11.50%
C000209587 [Member] | Diversified [Member]  
Holdings [Line Items]  
Percent of Total Investments 44.00%
C000209586 [Member] | Williams Cos Inc The [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.07% [21]
C000209586 [Member] | ONEOK Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.32% [21]
C000209586 [Member] | Plains All American Pipeline L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 10.31% [21]
C000209586 [Member] | Targa Resources Corp [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 13.33% [21]
C000209586 [Member] | Enterprise Products Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 13.97% [21]
C000209586 [Member] | Western Midstream Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 14.74% [21]
C000209586 [Member] | Energy Transfer L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 16.94% [21]
C000209586 [Member] | MPLX L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 17.34% [21]
C000209586 [Member] | Hess Midstream L P Class A [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 7.46% [21]
C000209586 [Member] | Sunoco L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 7.20% [21]
C000209586 [Member] | Natural Gas Pipeline Transportation [Member]  
Holdings [Line Items]  
Percent of Total Investments 2.70%
C000209586 [Member] | Other Energy Equipment [Member]  
Holdings [Line Items]  
Percent of Total Investments 15.70%
C000209586 [Member] | Gas Gathering and Processing Equipment [Member]  
Holdings [Line Items]  
Percent of Total Investments 26.10%
C000209586 [Member] | Petroleum Products [Member]  
Holdings [Line Items]  
Percent of Total Investments 11.50%
C000209586 [Member] | Diversified [Member]  
Holdings [Line Items]  
Percent of Total Investments 44.00%
C000209585 [Member] | Williams Cos Inc The [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.07% [22]
C000209585 [Member] | ONEOK Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.32% [22]
C000209585 [Member] | Plains All American Pipeline L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 10.31% [22]
C000209585 [Member] | Targa Resources Corp [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 13.33% [22]
C000209585 [Member] | Enterprise Products Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 13.97% [22]
C000209585 [Member] | Western Midstream Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 14.74% [22]
C000209585 [Member] | Energy Transfer L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 16.94% [22]
C000209585 [Member] | MPLX L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 17.34% [22]
C000209585 [Member] | Hess Midstream L P Class A [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 7.46% [22]
C000209585 [Member] | Sunoco L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 7.20% [22]
C000209585 [Member] | Natural Gas Pipeline Transportation [Member]  
Holdings [Line Items]  
Percent of Total Investments 2.70%
C000209585 [Member] | Other Energy Equipment [Member]  
Holdings [Line Items]  
Percent of Total Investments 15.70%
C000209585 [Member] | Gas Gathering and Processing Equipment [Member]  
Holdings [Line Items]  
Percent of Total Investments 26.10%
C000209585 [Member] | Petroleum Products [Member]  
Holdings [Line Items]  
Percent of Total Investments 11.50%
C000209585 [Member] | Diversified [Member]  
Holdings [Line Items]  
Percent of Total Investments 44.00%
C000209584 [Member] | Williams Cos Inc The [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.07% [23]
C000209584 [Member] | ONEOK Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.32% [23]
C000209584 [Member] | Plains All American Pipeline L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 10.31% [23]
C000209584 [Member] | Targa Resources Corp [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 13.33% [23]
C000209584 [Member] | Enterprise Products Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 13.97% [23]
C000209584 [Member] | Western Midstream Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 14.74% [23]
C000209584 [Member] | Energy Transfer L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 16.94% [23]
C000209584 [Member] | MPLX L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 17.34% [23]
C000209584 [Member] | Hess Midstream L P Class A [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 7.46% [23]
C000209584 [Member] | Sunoco L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 7.20% [23]
C000209584 [Member] | Natural Gas Pipeline Transportation [Member]  
Holdings [Line Items]  
Percent of Total Investments 2.70%
C000209584 [Member] | Other Energy Equipment [Member]  
Holdings [Line Items]  
Percent of Total Investments 15.70%
C000209584 [Member] | Gas Gathering and Processing Equipment [Member]  
Holdings [Line Items]  
Percent of Total Investments 26.10%
C000209584 [Member] | Petroleum Products [Member]  
Holdings [Line Items]  
Percent of Total Investments 11.50%
C000209584 [Member] | Diversified [Member]  
Holdings [Line Items]  
Percent of Total Investments 44.00%
C000209583 [Member] | Williams Cos Inc The [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.07% [24]
C000209583 [Member] | ONEOK Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.32% [24]
C000209583 [Member] | Plains All American Pipeline L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 10.31% [24]
C000209583 [Member] | Targa Resources Corp [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 13.33% [24]
C000209583 [Member] | Enterprise Products Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 13.97% [24]
C000209583 [Member] | Western Midstream Partners L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 14.74% [24]
C000209583 [Member] | Energy Transfer L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 16.94% [24]
C000209583 [Member] | MPLX L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 17.34% [24]
C000209583 [Member] | Hess Midstream L P Class A [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 7.46% [24]
C000209583 [Member] | Sunoco L P [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 7.20% [24]
C000209583 [Member] | Natural Gas Pipeline Transportation [Member]  
Holdings [Line Items]  
Percent of Total Investments 2.70%
C000209583 [Member] | Other Energy Equipment [Member]  
Holdings [Line Items]  
Percent of Total Investments 15.70%
C000209583 [Member] | Gas Gathering and Processing Equipment [Member]  
Holdings [Line Items]  
Percent of Total Investments 26.10%
C000209583 [Member] | Petroleum Products [Member]  
Holdings [Line Items]  
Percent of Total Investments 11.50%
C000209583 [Member] | Diversified [Member]  
Holdings [Line Items]  
Percent of Total Investments 44.00%
[1] Excluding money market fund holdings, if any.
[2] Excluding money market fund holdings, if any.
[3] Excluding money market fund holdings, if any.
[4] Excluding money market fund holdings, if any.
[5] Excluding money market fund holdings, if any.
[6] Excluding money market fund holdings, if any.
[7] Excluding money market fund holdings, if any.
[8] Excluding money market fund holdings, if any.
[9] Excluding money market fund holdings, if any.
[10] Excluding money market fund holdings, if any.
[11] Excluding money market fund holdings, if any.
[12] Excluding money market fund holdings, if any.
[13] Excluding money market fund holdings, if any.
[14] Excluding money market fund holdings, if any.
[15] Excluding money market fund holdings, if any.
[16] Excluding money market fund holdings, if any.
[17] Excluding money market fund holdings, if any.
[18] Excluding money market fund holdings, if any.
[19] Excluding money market fund holdings, if any.
[20] Excluding money market fund holdings, if any.
[21] Excluding money market fund holdings, if any.
[22] Excluding money market fund holdings, if any.
[23] Excluding money market fund holdings, if any.
[24] Excluding money market fund holdings, if any.