Class A Class A | MSCI World Index - net Class A | FTSE Global Core Infrastructure 50/50 Net Tax Index Investment Type [Axis] NextEra Energy, Inc. Williams Cos., Inc. TC Energy Corp. Entergy Corp. Union Pacific Corp. CSX Corp. American Electric Power Co., Inc. National Grid PLC Norfolk Southern Corp. Targa Resources Corp. Electric Midstream Railways Airports Gas Distribution [Member] Marine Ports Communications Toll Roads Environmental Services Other (includes short-term investments) UNITED STATES CANADA AUSTRALIA JAPAN SPAIN INDIA UNITED KINGDOM BRAZIL PHILIPPINES Class C Class C | MSCI World Index - net Class C | FTSE Global Core Infrastructure 50/50 Net Tax Index Class I Class I | MSCI World Index - net Class I | FTSE Global Core Infrastructure 50/50 Net Tax Index Class R Class R | MSCI World Index - net Class R | FTSE Global Core Infrastructure 50/50 Net Tax Index Class Z Class Z | MSCI World Index - net Class Z | FTSE Global Core Infrastructure 50/50 Net Tax Index Net Assets Investment Company, Portfolio Turnover