Shareholder Report, Holdings (Details)	Apr. 30, 2025
C000112720 \| 87612G101 \| Targa Resources Corporation
Holdings [Line Items]
Percent of Net Asset Value	11.30%
C000112720 \| 72651A207 \| Plains GP Holdings, L.P., Class A
Holdings [Line Items]
Percent of Net Asset Value	11.00%
C000112720 \| 29273V100 \| Energy Transfer, L.P.
Holdings [Line Items]
Percent of Net Asset Value	9.90%
C000112720 \| 16411R208 \| Cheniere Energy, Inc.
Holdings [Line Items]
Percent of Net Asset Value	7.80%
C000112720 \| 958669103 \| Western Midstream Partners, L.P.
Holdings [Line Items]
Percent of Net Asset Value	7.00%
C000112720 \| 49456B101 \| Kinder Morgan, Inc.
Holdings [Line Items]
Percent of Net Asset Value	4.90%
C000112720 \| 969457100 \| Williams Companies, Inc. (The)
Holdings [Line Items]
Percent of Net Asset Value	4.90%
C000112720 \| 23345M107 \| DT Midstream, Inc.
Holdings [Line Items]
Percent of Net Asset Value	4.90%
C000112720 \| 87807B107 \| TC Energy Corporation
Holdings [Line Items]
Percent of Net Asset Value	4.90%
C000112720 \| 428103105 \| Hess Midstream, L.P., Class A
Holdings [Line Items]
Percent of Net Asset Value	4.80%
C000112720 \| Energy23345M107
Holdings [Line Items]
Percent of Total Investments	98.40%
C000112720 \| Cash & Equivalent31846V336
Holdings [Line Items]
Percent of Total Investments	1.60%
C000112720 \| Money Market Funds
Holdings [Line Items]
Percent of Net Asset Value	1.60%
C000112720 \| Utilities
Holdings [Line Items]
Percent of Net Asset Value	2.90%
C000112720 \| Energy
Holdings [Line Items]
Percent of Net Asset Value	94.70%
C000124015 \| 87612G101 \| Targa Resources Corporation
Holdings [Line Items]
Percent of Net Asset Value	11.30%
C000124015 \| 72651A207 \| Plains GP Holdings, L.P., Class A
Holdings [Line Items]
Percent of Net Asset Value	11.00%
C000124015 \| 29273V100 \| Energy Transfer, L.P.
Holdings [Line Items]
Percent of Net Asset Value	9.90%
C000124015 \| 16411R208 \| Cheniere Energy, Inc.
Holdings [Line Items]
Percent of Net Asset Value	7.80%
C000124015 \| 958669103 \| Western Midstream Partners, L.P.
Holdings [Line Items]
Percent of Net Asset Value	7.00%
C000124015 \| 49456B101 \| Kinder Morgan, Inc.
Holdings [Line Items]
Percent of Net Asset Value	4.90%
C000124015 \| 969457100 \| Williams Companies, Inc. (The)
Holdings [Line Items]
Percent of Net Asset Value	4.90%
C000124015 \| 23345M107 \| DT Midstream, Inc.
Holdings [Line Items]
Percent of Net Asset Value	4.90%
C000124015 \| 87807B107 \| TC Energy Corporation
Holdings [Line Items]
Percent of Net Asset Value	4.90%
C000124015 \| 428103105 \| Hess Midstream, L.P., Class A
Holdings [Line Items]
Percent of Net Asset Value	4.80%
C000124015 \| Energy23345M107
Holdings [Line Items]
Percent of Total Investments	98.40%
C000124015 \| Cash & Equivalent31846V336
Holdings [Line Items]
Percent of Total Investments	1.60%
C000124015 \| Money Market Funds
Holdings [Line Items]
Percent of Net Asset Value	1.60%
C000124015 \| Utilities
Holdings [Line Items]
Percent of Net Asset Value	2.90%
C000124015 \| Energy
Holdings [Line Items]
Percent of Net Asset Value	94.70%
C000112721 \| 87612G101 \| Targa Resources Corporation
Holdings [Line Items]
Percent of Net Asset Value	11.30%
C000112721 \| 72651A207 \| Plains GP Holdings, L.P., Class A
Holdings [Line Items]
Percent of Net Asset Value	11.00%
C000112721 \| 29273V100 \| Energy Transfer, L.P.
Holdings [Line Items]
Percent of Net Asset Value	9.90%
C000112721 \| 16411R208 \| Cheniere Energy, Inc.
Holdings [Line Items]
Percent of Net Asset Value	7.80%
C000112721 \| 958669103 \| Western Midstream Partners, L.P.
Holdings [Line Items]
Percent of Net Asset Value	7.00%
C000112721 \| 49456B101 \| Kinder Morgan, Inc.
Holdings [Line Items]
Percent of Net Asset Value	4.90%
C000112721 \| 969457100 \| Williams Companies, Inc. (The)
Holdings [Line Items]
Percent of Net Asset Value	4.90%
C000112721 \| 23345M107 \| DT Midstream, Inc.
Holdings [Line Items]
Percent of Net Asset Value	4.90%
C000112721 \| 87807B107 \| TC Energy Corporation
Holdings [Line Items]
Percent of Net Asset Value	4.90%
C000112721 \| 428103105 \| Hess Midstream, L.P., Class A
Holdings [Line Items]
Percent of Net Asset Value	4.80%
C000112721 \| Energy23345M107
Holdings [Line Items]
Percent of Total Investments	98.40%
C000112721 \| Cash & Equivalent31846V336
Holdings [Line Items]
Percent of Total Investments	1.60%
C000112721 \| Money Market Funds
Holdings [Line Items]
Percent of Net Asset Value	1.60%
C000112721 \| Utilities
Holdings [Line Items]
Percent of Net Asset Value	2.90%
C000112721 \| Energy
Holdings [Line Items]
Percent of Net Asset Value	94.70%
C000203318 \| 87612G101 \| Targa Resources Corporation
Holdings [Line Items]
Percent of Net Asset Value	11.30%
C000203318 \| 72651A207 \| Plains GP Holdings, L.P., Class A
Holdings [Line Items]
Percent of Net Asset Value	11.00%
C000203318 \| 29273V100 \| Energy Transfer, L.P.
Holdings [Line Items]
Percent of Net Asset Value	9.90%
C000203318 \| 16411R208 \| Cheniere Energy, Inc.
Holdings [Line Items]
Percent of Net Asset Value	7.80%
C000203318 \| 958669103 \| Western Midstream Partners, L.P.
Holdings [Line Items]
Percent of Net Asset Value	7.00%
C000203318 \| 49456B101 \| Kinder Morgan, Inc.
Holdings [Line Items]
Percent of Net Asset Value	4.90%
C000203318 \| 969457100 \| Williams Companies, Inc. (The)
Holdings [Line Items]
Percent of Net Asset Value	4.90%
C000203318 \| 23345M107 \| DT Midstream, Inc.
Holdings [Line Items]
Percent of Net Asset Value	4.90%
C000203318 \| 87807B107 \| TC Energy Corporation
Holdings [Line Items]
Percent of Net Asset Value	4.90%
C000203318 \| 428103105 \| Hess Midstream, L.P., Class A
Holdings [Line Items]
Percent of Net Asset Value	4.80%
C000203318 \| Energy23345M107
Holdings [Line Items]
Percent of Total Investments	98.40%
C000203318 \| Cash & Equivalent31846V336
Holdings [Line Items]
Percent of Total Investments	1.60%
C000203318 \| Money Market Funds
Holdings [Line Items]
Percent of Net Asset Value	1.60%
C000203318 \| Utilities
Holdings [Line Items]
Percent of Net Asset Value	2.90%
C000203318 \| Energy
Holdings [Line Items]
Percent of Net Asset Value	94.70%

Shareholder Report, Holdings (Details)

Apr. 30, 2025