v3.26.1
Condensed Schedules of Investments - USD ($)
Jun. 30, 2026
Mar. 31, 2026
Schedule of Investments [Line Items]    
Fair Value $ 186,519,761 $ 183,338,199
Macquarie Infrastructure Fund, L.P    
Schedule of Investments [Line Items]    
Cost 9,846,980 49,548
Fair Value $ 94,055,758 $ 11,073,581
Fair Value as a Percentage of Net Assets 6.80% 1.24%
MIF Cayman, L.P.    
Schedule of Investments [Line Items]    
Cost $ 1,002,713,098 $ 763,562,434
Fair Value $ 210,494,937 $ 37,429,665
Fair Value as a Percentage of Net Assets 5.00% 5.00%
MIF Cayman, L.P. | Americas [Member]    
Schedule of Investments [Line Items]    
Cost   $ 409,773,497
MIF Cayman, L.P. | EMEA [Member]    
Schedule of Investments [Line Items]    
Cost   260,505,420
MIF Cayman, L.P. | APAC [Member]    
Schedule of Investments [Line Items]    
Cost   81,235,907
Various [Member] | MIF Cayman, L.P.    
Schedule of Investments [Line Items]    
Cost   50,730,409
Investment, Identifier [Axis]: Derivative instruments Foreign currency forward contract | Macquarie Infrastructure Fund, L.P    
Schedule of Investments [Line Items]    
Fair Value $ 1,072,485 17,663
Fair Value as a Percentage of Net Assets 1.07%  
Investment, Identifier [Axis]: NOI IAIIAF Debt investments Various Other investments Type of Investment Debt investment Geography Various | MIF Cayman, L.P.    
Schedule of Investments [Line Items]    
Fair Value [1] $ 14,802,300 [2],[3] $ 34,577,371 [4]
Fair Value as a Percentage of Net Assets [1] 1.07% [2],[3] 3.86% [4]
Investment, Identifier [Axis]: NOI IAIIAF Equity investments Digital Aligned Data Centers Holding entity Aligned Co-Invest Aggregator, L.P. Type of Investment Equity investment Geography Americas | MIF Cayman, L.P.    
Schedule of Investments [Line Items]    
Fair Value $ 186,519,761 [2],[5] $ 183,338,199 [6],[7]
Fair Value as a Percentage of Net Assets 13.48% [2],[5] 20.49% [6],[7]
Investment, Identifier [Axis]: NOI IAIIAF Equity investments Digital Applied Digital Corporation Holding entity MIP HPC Feeder, L.P. Type of Investment Equity investment Geography Americas | MIF Cayman, L.P.    
Schedule of Investments [Line Items]    
Fair Value [2],[3] $ 157,008,909  
Fair Value as a Percentage of Net Assets [2],[3] 11.35%  
Investment, Identifier [Axis]: NOI IAIIAF Equity investments Digital Vocus Group Holding entity Voyage MAIF3 Consortium Trust Type of Investment Equity investment Geography APAC | MIF Cayman, L.P.    
Schedule of Investments [Line Items]    
Fair Value $ 89,601,202 [2],[8] $ 87,950,865 [6],[9]
Fair Value as a Percentage of Net Assets 6.48% [2],[8] 9.83% [6],[9]
Investment, Identifier [Axis]: NOI IAIIAF Equity investments Green energy D. E. Shaw Renewable Investments Holding entity MGIF Hobbs Holdings L.P. Type of Investment Equity investment Geography Americas | MIF Cayman, L.P.    
Schedule of Investments [Line Items]    
Fair Value $ 186,710,010 [2],[10] $ 166,495,564 [6],[11]
Fair Value as a Percentage of Net Assets 13.50% [2],[10] 18.61% [6],[11]
Investment, Identifier [Axis]: NOI IAIIAF Equity investments Green energy Island Green Power Holding entity MIF Cooks Holdings S.à r.l. Type of Investment Equity investment Geography EMEA | MIF Cayman, L.P.    
Schedule of Investments [Line Items]    
Fair Value $ 95,574,405 [2],[12] $ 90,653,904 [6],[13]
Fair Value as a Percentage of Net Assets 6.91% [2],[12] 10.13% [6],[13]
Investment, Identifier [Axis]: NOI IAIIAF Equity investments Transport Bristol and Birmingham Airports Holding entity MEIF 7 Homecoming Regional Ventures S.à r.l. Type of Investment Equity investment Geography EMEA | MIF Cayman, L.P.    
Schedule of Investments [Line Items]    
Fair Value [2],[14] $ 46,183,756  
Fair Value as a Percentage of Net Assets [2],[14] 3.34%  
Investment, Identifier [Axis]: NOI IAIIAF Equity investments Transport Other investments Holding entity Type of Investment Equity investment Geography EMEA | MIF Cayman, L.P.    
Schedule of Investments [Line Items]    
Fair Value [2],[15] $ 27,937,337  
Fair Value as a Percentage of Net Assets [2],[15] 2.02%  
Investment, Identifier [Axis]: NOI IAIIAF Equity investments Utilities and energy Diamond Infrastructure Solutions Holding entity InfraPark CI Blocker LLC Type of Investment Equity investment Geography Americas | MIF Cayman, L.P.    
Schedule of Investments [Line Items]    
Fair Value $ 99,537,826 [2],[16] $ 97,739,702 [6],[17]
Fair Value as a Percentage of Net Assets 7.19% [2],[16] 10.92% [6],[17]
Investment, Identifier [Axis]: NOI IAIIAF Equity investments Utilities and energy Last Mile Infrastructure Holding entity MGIF Connex Investments S.à r.l. Type of Investment Equity investment Geography EMEA | MIF Cayman, L.P.    
Schedule of Investments [Line Items]    
Fair Value [2],[18] $ 87,983,570  
Fair Value as a Percentage of Net Assets [2],[18] 6.36%  
Investment, Identifier [Axis]: NOI IAIIAF Equity investments Utilities and energy Southern Water Holding entity MSCIF Sandstone Ventures S.à r.l. Type of Investment Equity investment Geography EMEA | MIF Cayman, L.P.    
Schedule of Investments [Line Items]    
Fair Value $ 109,716,554 [2],[19] $ 72,028,335 [6],[20]
Fair Value as a Percentage of Net Assets 7.93% [2],[19] 8.05% [6],[20]
Investment, Identifier [Axis]: NOI IAIIAF Equity investments Waste Other investments Holding entity Type of Investment Geography EMEA | MIF Cayman, L.P.    
Schedule of Investments [Line Items]    
Fair Value [2],[15] $ 61,935,367  
Fair Value as a Percentage of Net Assets [2],[15] 4.48%  
Investment, Identifier [Axis]: NOI IAIIAF Equity investments Waste Renewi Holding entity MIF Earth Holdings S.à r.l Type of Investment Equity investment Geography EMEA | MIF Cayman, L.P.    
Schedule of Investments [Line Items]    
Fair Value [6],[21]   $ 60,284,692
Fair Value as a Percentage of Net Assets [6],[21]   6.74%
Investment, Identifier [Axis]: NOI IAIIAF Investments in affiliated fund Various Macquarie Global Infrastructure Fund (USD Feeder) SCSp Type of Investment LP interest Geography EMEA | MIF Cayman, L.P.    
Schedule of Investments [Line Items]    
Fair Value   $ 37,429,665
Fair Value as a Percentage of Net Assets   4.18%
Investment, Identifier [Axis]: NOI IAIIAF Other equity investments Various Other investments Type of Investment Equity investment Geography Various | MIF Cayman, L.P.    
Schedule of Investments [Line Items]    
Fair Value [2],[4]   $ 15,708,116
Fair Value as a Percentage of Net Assets [2],[4]   1.76%
Investment, Identifier [Axis]: NOI IAIIAF Transport Bristol and Birmingham Airports Type of Investment Equity investment Geography EMEA | MIF Cayman, L.P.    
Schedule of Investments [Line Items]    
Fair Value [6],[22]   $ 44,755,488
Fair Value as a Percentage of Net Assets [6],[22]   5.00%
Investment, Identifier [Axis]: Name of Investment Investments and investments in affiliated fund Investments in affiliated fund Various Macquarie Global Infrastructure Fund (USD Feeder) Type of Investment LP interest Geography EMEA | MIF Cayman, L.P.    
Schedule of Investments [Line Items]    
Fair Value $ 210,494,937  
Fair Value as a Percentage of Net Assets 15.21%  
Investment, Identifier [Axis]: Name of Investment Investments in affiliated fund MIF Cayman, L.P Type of Investment LP interest Geography Various Industry Various | Macquarie Infrastructure Fund, L.P    
Schedule of Investments [Line Items]    
Fair Value [23] $ 94,055,758 $ 11,073,581
Fair Value as a Percentage of Net Assets [23] 94.21% 155.61%
Investment, Identifier [Axis]: Name of Investment Treasury Bills Type of Investment Government bonds Geography Americas | Macquarie Infrastructure Fund, L.P    
Schedule of Investments [Line Items]    
Fair Value $ 9,845,036 $ 49,854
Fair Value as a Percentage of Net Assets 9.86% 0.70%
Government bonds [Member] | Macquarie Infrastructure Fund, L.P    
Schedule of Investments [Line Items]    
Fair Value $ 9,845,036 $ 49,854
Fair Value as a Percentage of Net Assets 9.86% 0.70%
Derivative instruments [Member] | Macquarie Infrastructure Fund, L.P    
Schedule of Investments [Line Items]    
Fair Value $ 1,072,485 $ 17,663
Fair Value as a Percentage of Net Assets 1.07% 0.25%
Other Equity Investments [Member] | MIF Cayman, L.P.    
Schedule of Investments [Line Items]    
Fair Value [2]   $ 15,708,116
Fair Value as a Percentage of Net Assets [2]   1.76%
Debt Investments [Member] | MIF Cayman, L.P.    
Schedule of Investments [Line Items]    
Cost $ 15,523,354  
Fair Value $ 14,802,300 [24] $ 34,577,371 [1]
Fair Value as a Percentage of Net Assets 1.07% [24] 3.86% [1]
Debt Investments [Member] | Various [Member] | MIF Cayman, L.P.    
Schedule of Investments [Line Items]    
Cost   $ 33,959,226
Affiliated fund [Member] | Macquarie Infrastructure Fund, L.P    
Schedule of Investments [Line Items]    
Fair Value $ 94,055,758 $ 11,073,581
Fair Value as a Percentage of Net Assets 94.21% 155.61%
Affiliated fund [Member] | MIF Cayman, L.P.    
Schedule of Investments [Line Items]    
Fair Value $ 210,494,937 $ 37,429,665
Fair Value as a Percentage of Net Assets 15.21% 4.18%
Affiliated fund [Member] | MIF Cayman, L.P. | EMEA [Member]    
Schedule of Investments [Line Items]    
Cost $ 210,574,024 $ 38,682,799
Total investments [Member] | MIF Cayman, L.P.    
Schedule of Investments [Line Items]    
Fair Value $ 1,163,510,997 $ 853,532,236
Fair Value as a Percentage of Net Assets 84.11% 95.39%
Total investments [Member] | MIF Cayman, L.P. | Americas [Member]    
Schedule of Investments [Line Items]    
Cost $ 549,363,725 $ 409,773,497
Total investments [Member] | MIF Cayman, L.P. | EMEA [Member]    
Schedule of Investments [Line Items]    
Cost 356,590,112 221,822,621
Total investments [Member] | MIF Cayman, L.P. | APAC [Member]    
Schedule of Investments [Line Items]    
Cost 81,235,907 81,235,907
Total investments [Member] | Various [Member] | MIF Cayman, L.P.    
Schedule of Investments [Line Items]    
Cost 15,523,354 50,730,409
Total Equity investments [Member] | MIF Cayman, L.P.    
Schedule of Investments [Line Items]    
Fair Value $ 1,148,708,697 [2] $ 818,954,865 [6]
Fair Value as a Percentage of Net Assets 83.04% [2] 91.53% [6]
Total Equity investments [Member] | MIF Cayman, L.P. | Americas [Member]    
Schedule of Investments [Line Items]    
Cost $ 549,363,725 $ 409,773,497
Total Equity investments [Member] | MIF Cayman, L.P. | EMEA [Member]    
Schedule of Investments [Line Items]    
Cost 356,590,112 221,822,621
Total Equity investments [Member] | MIF Cayman, L.P. | APAC [Member]    
Schedule of Investments [Line Items]    
Cost 81,235,907 81,235,907
Total Equity investments [Member] | Various [Member] | MIF Cayman, L.P.    
Schedule of Investments [Line Items]    
Cost   16,771,183
Equity investments [Member] | MIF Cayman, L.P.    
Schedule of Investments [Line Items]    
Fair Value [2] $ 433,129,872  
Fair Value as a Percentage of Net Assets [2] 31.31%  
Equity investments [Member] | Green energy [Member] | MIF Cayman, L.P.    
Schedule of Investments [Line Items]    
Fair Value $ 282,284,415 [2] $ 257,149,468 [6]
Fair Value as a Percentage of Net Assets 20.41% [2] 28.74% [6]
Equity investments [Member] | Utilities and energy [Member] | MIF Cayman, L.P.    
Schedule of Investments [Line Items]    
Fair Value $ 297,237,950 [2] $ 169,768,037 [6]
Fair Value as a Percentage of Net Assets 21.48% [2] 18.97% [6]
Equity investments [Member] | Waste [Member] | MIF Cayman, L.P.    
Schedule of Investments [Line Items]    
Fair Value $ 61,935,367 [2] $ 60,284,692 [6]
Fair Value as a Percentage of Net Assets 4.48% [2] 6.74% [6]
Equity investments [Member] | Digital [Member] | MIF Cayman, L.P.    
Schedule of Investments [Line Items]    
Fair Value [6]   $ 271,289,064
Fair Value as a Percentage of Net Assets [6]   30.32%
Equity investments [Member] | Transport [Member] | MIF Cayman, L.P.    
Schedule of Investments [Line Items]    
Fair Value $ 74,121,093 [2] $ 44,755,488 [6]
Fair Value as a Percentage of Net Assets 5.36% [2] 5.00% [6]
Total investments in affiliated fund and investments [Member] | Macquarie Infrastructure Fund, L.P    
Schedule of Investments [Line Items]    
Fair Value $ 103,900,794 $ 11,123,435
Fair Value as a Percentage of Net Assets 104.07% 156.31%
Total investments in affiliated fund and investments [Member] | Macquarie Infrastructure Fund, L.P | Americas [Member]    
Schedule of Investments [Line Items]    
Cost $ 9,846,980 $ 49,548
Total investments in affiliated fund and investments [Member] | MIF Cayman, L.P.    
Schedule of Investments [Line Items]    
Fair Value $ 1,374,005,934 $ 890,961,901
Fair Value as a Percentage of Net Assets 99.32% 99.57%
Total investments in affiliated fund and investments [Member] | MIF Cayman, L.P. | Americas [Member]    
Schedule of Investments [Line Items]    
Cost $ 549,363,725  
Total investments in affiliated fund and investments [Member] | MIF Cayman, L.P. | EMEA [Member]    
Schedule of Investments [Line Items]    
Cost 567,164,136  
Total investments in affiliated fund and investments [Member] | MIF Cayman, L.P. | APAC [Member]    
Schedule of Investments [Line Items]    
Cost 81,235,907  
Total investments in affiliated fund and investments [Member] | Various [Member] | Macquarie Infrastructure Fund, L.P    
Schedule of Investments [Line Items]    
Cost 89,051,454 $ 9,805,183
Total investments in affiliated fund and investments [Member] | Various [Member] | MIF Cayman, L.P.    
Schedule of Investments [Line Items]    
Cost $ 15,523,354  
[1] Debt investments include different forms of interests that represent a creditor relationship with an investee, including but not limited to (1) bank loans, (2) interests in collateralized loan obligations and (3) direct lending debt investments.
[2] Equity investments generally include different forms of interests and rights and obligations that represent ownership in an entity or the right to acquire or dispose of ownership in an entity, including but not limited to (1) common equity, (2) preferred equity, (3) limited partner interests, (4) warrants and (5) other equity-linked securities.
[3] The Aggregator holds an indirect equity interest in Applied Digital Corporation through its 47.30% ownership in MIP HPC Feeder, L.P.
[4] There were no single investments included in this category that exceeded 5% of the net assets of the Aggregator.
[5] The Aggregator holds an indirect equity interest in Aligned Data Centers through its 5.35% ownership in Aligned Co-Invest Aggregator, L.P.
[6] Equity investments generally include different forms of interests and rights and obligations that represent ownership in an entity or the right to acquire or dispose of ownership in an entity, including but not limited to (1) common equity, (2) preferred equity, (3) limited partner interests, (4) warrants and (5) other equity-linked securities.
[7] The Aggregator holds an indirect equity interest in Aligned Data Centers through its 3.74% ownership in Aligned Co-Invest Aggregator, L.P.
[8] The Aggregator holds an indirect equity interest in Vocus Group through its 3.40% ownership in Voyage MAIF3 Consortium Trust.
[9] The Aggregator holds an indirect equity interest in Vocus Group through its 3.40% ownership in Voyage MAIF3 Consortium Trust.
[10] The Aggregator holds an indirect equity interest in D. E. Shaw Renewable Investments through its 13.29% ownership in MGIF Hobbs Holdings LLC. The Aggregator holds an additional indirect equity interest in D. E. Shaw Renewable Investments through its 39.95% holding in Macquarie Global Infrastructure Fund (USD Feeder) SCSp.
[11] The Aggregator holds an indirect equity interest in D. E. Shaw Renewable Investments through its 13.29% ownership in MGIF Hobbs Holdings LLC. The Aggregator holds an additional indirect equity interest in D. E. Shaw Renewable Investments of 2.55% through its 10.76% holding in Macquarie Global Infrastructure Fund (USD Feeder) SCSp.
[12] The Aggregator holds an indirect equity interest in Island Green Power through its 40.83% ownership of MGREF 2 Cooks Holdings 2 Limited.
[13] The Aggregator holds an indirect equity interest in Island Green Power through its 40.83% ownership of MGREF 2 Cooks Holdings 2 Limited.
[14] The Aggregator holds an indirect equity interest in Bristol and Birmingham Airports through its 2.84% ownership in MEIF 7 Homecoming Regional Ventures S.à r.l.
[15] There were no single investments included in this category that exceeded 5% of the net assets of the Aggregator.
[16] The Aggregator holds an indirect equity interest in Diamond Infrastructure Solutions through its 13.28% ownership in InfraPark CI Blocker, LLC.
[17] The Aggregator holds an indirect equity interest in Diamond Infrastructure Solutions through its 13.60% ownership in InfraPark CI Blocker, LLC.
[18] The Aggregator holds an indirect equity interest in Last Mile Infrastructure through its 13.00% ownership in MGIF Connex Investments S.à r.l.
[19] The Aggregator holds an indirect equity interest in Southern Water through its 3.47% ownership in MSCIF Sandstone Ventures S.à r.l.
[20] The Aggregator holds an indirect equity interest in Southern Water through its 2.34% ownership in MSCIF Sandstone Ventures S.à r.l.
[21] The Aggregator holds an indirect equity interest in Renewi through its 100% ownership in MIF Earth Holdings S.à r.l.
[22] The Aggregator holds an indirect equity interest in Bristol and Birmingham Airports through its 2.84% ownership in MEIF 7 Homecoming Regional Ventures S.à r.l.
[23] The Fund had an interest of 6.80% and 1.24% in MIF Cayman, L.P. as of June 30, 2026 and March 31, 2026, respectively.
[24] Debt investments includes different forms of interests that represent a creditor relationship with an investee, including but not limited to (1) bank loans, (2) interests in collateralized loan obligations and (3) direct lending debt investments.