v3.25.2
Shareholder Report, Holdings (Details)
May 31, 2025
C000142690 [Member] | Energy Transfer LP [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 9.10% [1]
C000142690 [Member] | Cheniere Energy Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 7.80% [1]
C000142690 [Member] | ONEOK Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 7.70% [1]
C000142690 [Member] | Targa Resources Corp [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 7.40% [1]
C000142690 [Member] | MPLX LP [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.70% [1]
C000142690 [Member] | Hess Midstream LP Class A [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.50% [1]
C000142690 [Member] | DT Midstream Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.40% [1]
C000142690 [Member] | Williams Cos Inc The [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 4.90% [1]
C000142690 [Member] | Kinder Morgan Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 4.90% [1]
C000142690 [Member] | TC Energy Corp [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 4.70% [1]
C000142690 [Member] | Utilities Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.10%
C000142690 [Member] | Large Cap Diversified C Corps [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 40.60%
C000142690 [Member] | Large Cap MLP [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 19.50%
C000142690 [Member] | Natural Gas Gatherers And Processors [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 18.20%
C000142690 [Member] | Natural Gas Transportation And Storage [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.40%
C000142690 [Member] | Crude Oil And Refined Products [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.60%
C000142690 [Member] | Other Corp [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.50%
C000142690 [Member] | Refiners [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.90%
C000142690 [Member] | Canadian Midstream [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.70%
C000142690 [Member] | YieldCo [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.20%
C000142691 [Member] | Energy Transfer LP [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 9.10% [2]
C000142691 [Member] | Cheniere Energy Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 7.80% [2]
C000142691 [Member] | ONEOK Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 7.70% [2]
C000142691 [Member] | Targa Resources Corp [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 7.40% [2]
C000142691 [Member] | MPLX LP [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.70% [2]
C000142691 [Member] | Hess Midstream LP Class A [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.50% [2]
C000142691 [Member] | DT Midstream Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.40% [2]
C000142691 [Member] | Williams Cos Inc The [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 4.90% [2]
C000142691 [Member] | Kinder Morgan Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 4.90% [2]
C000142691 [Member] | TC Energy Corp [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 4.70% [2]
C000142691 [Member] | Utilities Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.10%
C000142691 [Member] | Large Cap Diversified C Corps [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 40.60%
C000142691 [Member] | Large Cap MLP [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 19.50%
C000142691 [Member] | Natural Gas Gatherers And Processors [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 18.20%
C000142691 [Member] | Natural Gas Transportation And Storage [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.40%
C000142691 [Member] | Crude Oil And Refined Products [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.60%
C000142691 [Member] | Other Corp [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.50%
C000142691 [Member] | Refiners [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.90%
C000142691 [Member] | Canadian Midstream [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.70%
C000142691 [Member] | YieldCo [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.20%
C000142692 [Member] | Energy Transfer LP [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 9.10% [3]
C000142692 [Member] | Cheniere Energy Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 7.80% [3]
C000142692 [Member] | ONEOK Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 7.70% [3]
C000142692 [Member] | Targa Resources Corp [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 7.40% [3]
C000142692 [Member] | MPLX LP [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.70% [3]
C000142692 [Member] | Hess Midstream LP Class A [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.50% [3]
C000142692 [Member] | DT Midstream Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.40% [3]
C000142692 [Member] | Williams Cos Inc The [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 4.90% [3]
C000142692 [Member] | Kinder Morgan Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 4.90% [3]
C000142692 [Member] | TC Energy Corp [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 4.70% [3]
C000142692 [Member] | Utilities Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.10%
C000142692 [Member] | Large Cap Diversified C Corps [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 40.60%
C000142692 [Member] | Large Cap MLP [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 19.50%
C000142692 [Member] | Natural Gas Gatherers And Processors [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 18.20%
C000142692 [Member] | Natural Gas Transportation And Storage [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.40%
C000142692 [Member] | Crude Oil And Refined Products [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.60%
C000142692 [Member] | Other Corp [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.50%
C000142692 [Member] | Refiners [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.90%
C000142692 [Member] | Canadian Midstream [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.70%
C000142692 [Member] | YieldCo [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.20%
C000142693 [Member] | Energy Transfer LP [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 9.10% [4]
C000142693 [Member] | Cheniere Energy Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 7.80% [4]
C000142693 [Member] | ONEOK Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 7.70% [4]
C000142693 [Member] | Targa Resources Corp [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 7.40% [4]
C000142693 [Member] | MPLX LP [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.70% [4]
C000142693 [Member] | Hess Midstream LP Class A [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.50% [4]
C000142693 [Member] | DT Midstream Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.40% [4]
C000142693 [Member] | Williams Cos Inc The [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 4.90% [4]
C000142693 [Member] | Kinder Morgan Inc [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 4.90% [4]
C000142693 [Member] | TC Energy Corp [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 4.70% [4]
C000142693 [Member] | Utilities Sector [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.10%
C000142693 [Member] | Large Cap Diversified C Corps [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 40.60%
C000142693 [Member] | Large Cap MLP [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 19.50%
C000142693 [Member] | Natural Gas Gatherers And Processors [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 18.20%
C000142693 [Member] | Natural Gas Transportation And Storage [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 5.40%
C000142693 [Member] | Crude Oil And Refined Products [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.60%
C000142693 [Member] | Other Corp [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 3.50%
C000142693 [Member] | Refiners [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 2.90%
C000142693 [Member] | Canadian Midstream [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.70%
C000142693 [Member] | YieldCo [Member]  
Holdings [Line Items]  
Percent of Net Asset Value 1.20%
[1] Excluding short-term investments
[2] Excluding short-term investments
[3] Excluding short-term investments
[4] Excluding short-term investments