v3.26.1
Condensed Consolidated Schedule of Investments (Unaudited) (Parenthetical) - USD ($)
$ in Thousands
Mar. 31, 2026
Dec. 31, 2025
Infrastructure assets, percentage 88.50% 88.90%
Investments at cost $ 5,279,464 $ 4,649,579
Investments and cash equivalents, cost 6,330,835 5,627,016
Infrastructure Assets $ 6,185,617 $ 5,563,528
Investment, Identifier [Axis]: Avantus LLC | Equity Interest Held Through KKR Eight Mile Aggregator L.P. | Renewables | North America    
Infrastructure assets, percentage   5.20%
Infrastructure Assets   $ 323,809
Investment, Identifier [Axis]: CapeOmega OS | Equity Interest Held Through KKR Buoy Aggregator L.P. | Transportation    
Infrastructure assets, percentage 5.30%  
Infrastructure Assets $ 367,632  
Investment, Identifier [Axis]: CapeOmega OS | Equity Interest Held Through KKR Buoy Aggregator L.P. | Transportation | Europe    
Infrastructure assets, percentage   5.70%
Infrastructure Assets   $ 357,128
Investment, Identifier [Axis]: Greenvolt Energias Renovaveis SA | Equity Interest Held Through KKR GV Investor Aggregator L.P. | Renewables    
Infrastructure assets, percentage 5.50%  
Infrastructure Assets $ 384,577  
Investment, Identifier [Axis]: Greenvolt Energias Renovaveis SA | Equity Interest Held Through KKR GV Investor Aggregator L.P. | Renewables | Europe    
Infrastructure assets, percentage   6.30%
Infrastructure Assets   $ 392,004
Investment, Identifier [Axis]: Grove Education Partners Holdco Limited | Equity Interest Held Through KKR Percival Aggregator L.P. | Social Infrastructure    
Infrastructure assets, percentage 8.00% 8.70%
Infrastructure Assets $ 557,598 $ 544,721
Investment, Identifier [Axis]: Other Infrastructure Assets | Data Centers    
Infrastructure assets, percentage 6.40% [1],[2] 5.70% [3],[4]
Infrastructure Assets $ 449,922 [1],[2] $ 354,063 [3],[4]
Investment, Identifier [Axis]: Other Infrastructure Assets | Energy & Utilities    
Infrastructure assets, percentage 6.40% [1],[5] 4.80% [3],[6]
Infrastructure Assets $ 446,455 [1],[5] $ 299,280 [3],[6]
Investment, Identifier [Axis]: Other Infrastructure Assets | Fiber    
Infrastructure assets, percentage 2.70% [1] 2.90% [3]
Infrastructure Assets $ 190,848 [1] $ 183,779 [3]
Investment, Identifier [Axis]: Other Infrastructure Assets | Industrial Infrastructure    
Infrastructure assets, percentage 1.10% [1] 1.10% [3]
Infrastructure Assets $ 73,468 [1] $ 70,474 [3]
Investment, Identifier [Axis]: Other Infrastructure Assets | Midstream Infrastructure 1    
Infrastructure assets, percentage 3.00% [1] 3.50% [3]
Infrastructure Assets $ 211,802 [1] $ 217,512 [3]
Investment, Identifier [Axis]: Other Infrastructure Assets | Midstream Infrastructure 2    
Infrastructure assets, percentage 2.60% [1],[7] 2.90% [3],[8]
Infrastructure Assets $ 182,113 [1],[7] $ 181,248 [3],[8]
Investment, Identifier [Axis]: Other Infrastructure Assets | Other Infrastructure    
Infrastructure assets, percentage 2.50% [1],[9] 2.60% [3],[10]
Infrastructure Assets $ 173,279 [1],[9] $ 165,781 [3],[10]
Investment, Identifier [Axis]: Other Infrastructure Assets | Renewables    
Infrastructure assets, percentage 7.70% [1],[11] 3.10% [3]
Infrastructure Assets $ 537,051 [1],[11] $ 192,619 [3]
Investment, Identifier [Axis]: Other Infrastructure Assets | Social Infrastructure    
Infrastructure assets, percentage 0.50% [1] 0.60% [3]
Infrastructure Assets $ 36,313 [1] $ 37,786 [3]
Investment, Identifier [Axis]: Other Infrastructure Assets | Transportation    
Infrastructure assets, percentage [3],[12]   2.30%
Infrastructure Assets [3],[12]   $ 146,623
Investment, Identifier [Axis]: Other Infrastructure Assets | Transportation 1    
Infrastructure assets, percentage [1],[13] 3.00%  
Infrastructure Assets [1],[13] $ 210,701  
Investment, Identifier [Axis]: Other Infrastructure Assets | Transportation 2    
Infrastructure assets, percentage [1],[7] 0.40%  
Infrastructure Assets [1],[7] $ 31,415  
Investment, Identifier [Axis]: Other Infrastructure Assets | Waste    
Infrastructure assets, percentage [1] 4.70%  
Infrastructure Assets [1] $ 327,435  
Investment, Identifier [Axis]: Other Infrastructure Assets | Waste | Asia Pacific    
Infrastructure assets, percentage [3]   1.40%
Infrastructure Assets [3]   $ 85,723
Investment, Identifier [Axis]: Refresco Group B.V. | Equity Interest Held Through KKR Pegasus Aggregator G.P. | Industrial Infrastructure    
Infrastructure assets, percentage 5.60% 6.20%
Infrastructure Assets $ 394,641 $ 390,343
Investment, Identifier [Axis]: Smart Metering Systems Limited | Equity Interest Held Through KKR Sienna Aggregator L.P. | Energy & Utilities    
Infrastructure assets, percentage 5.00% [14] 5.80% [15]
Infrastructure Assets $ 347,343 [14] $ 364,499 [15]
Investment, Identifier [Axis]: Telecom Italia NetCo | Equity Interest Held Through Optics HoldCo Srl | Fiber    
Infrastructure assets, percentage 9.00% 9.90%
Infrastructure Assets $ 629,493 $ 616,585
Investment, Identifier [Axis]: Vantage Towers AG | Equity Interest Held Through KKR Oak Aggregator L.P. | Telecom Towers    
Infrastructure assets, percentage 9.10% 10.20%
Infrastructure Assets $ 633,531 $ 639,551
North America    
Infrastructure assets, percentage 19.30% 20.00%
Investments at cost $ 1,227,290 $ 1,141,290
Infrastructure Assets $ 1,361,583 $ 1,249,551
UNITED KINGDOM    
Infrastructure assets, percentage 17.20% 16.40%
Investments at cost $ 1,010,951 $ 798,653
Infrastructure Assets $ 1,191,685 $ 1,021,063
Europe    
Infrastructure assets, percentage 43.40% 47.70%
Investments at cost $ 2,497,933 $ 2,459,707
Infrastructure Assets $ 3,032,840 $ 2,987,918
Asia-Pacific    
Infrastructure assets, percentage 8.70% 4.80%
Investments at cost $ 543,290 $ 249,929
Infrastructure Assets 599,509 304,996
Money Market Funds    
Investments in money market funds, cost $ 1,051,371 $ 977,437
Data Centers    
Infrastructure assets, percentage 6.40% 5.70%
Data Centers | North America    
Infrastructure assets, percentage 73.60% 67.80%
Data Centers | UNITED KINGDOM    
Infrastructure assets, percentage 2.90% 3.00%
Data Centers | Asia-Pacific    
Infrastructure assets, percentage 23.50% 29.20%
Energy And Utilities    
Infrastructure assets, percentage 11.40% 10.60%
Energy And Utilities | North America    
Infrastructure assets, percentage 11.50% 16.90%
Energy And Utilities | UNITED KINGDOM    
Infrastructure assets, percentage 33.90%  
Energy And Utilities | Europe    
Infrastructure assets, percentage 54.20% 83.10%
Energy And Utilities | Asia-Pacific    
Infrastructure assets, percentage 0.40%  
Fiber    
Infrastructure assets, percentage 11.70% 12.80%
Industrial Infrastructure    
Infrastructure assets, percentage 6.70% 7.40%
Midstream Infrastructure    
Infrastructure assets, percentage 5.60% 6.40%
Other Infrastructure    
Infrastructure assets, percentage 2.50% 2.60%
Other Infrastructure | North America    
Infrastructure assets, percentage 2.00% 2.10%
Other Infrastructure | UNITED KINGDOM    
Infrastructure assets, percentage 30.90% 28.50%
Other Infrastructure | Europe    
Infrastructure assets, percentage 67.10% 69.40%
Renewables    
Infrastructure assets, percentage 13.20% 14.50%
Renewables | North America    
Infrastructure assets, percentage 63.50%  
Renewables | Europe    
Infrastructure assets, percentage 35.30%  
Renewables | Asia-Pacific    
Infrastructure assets, percentage 1.20%  
Social Infrastructure    
Infrastructure assets, percentage 8.50% 9.30%
Telecom Towers    
Infrastructure assets, percentage 9.10% 10.20%
Transportation    
Infrastructure assets, percentage 8.70% 8.00%
Transportation | North America    
Infrastructure assets, percentage 23.90% 33.50%
Transportation | UNITED KINGDOM    
Infrastructure assets, percentage 15.60% 11.10%
Transportation | Europe    
Infrastructure assets, percentage 35.30% 24.50%
Transportation | Asia-Pacific    
Infrastructure assets, percentage 25.20% 30.90%
Waste    
Infrastructure assets, percentage 4.70% 1.40%
[1]
(2) There were no single investments included in this category that exceeded 5% of net assets.
[2]
(4) 73.6% of fair value shown is domiciled in North America, 23.5% in Asia Pacific, and 2.9% in United Kingdom.
[3]
(2) There were no single investments included in this category that exceeded 5% of net assets.
[4]
(4) 67.8% of fair value shown is domiciled in North America, 29.2% in Asia Pacific, and 3.0% in United Kingdom.
[5]
(5) 0.4% of fair value shown is domiciled in Asia Pacific, 54.2% in Europe, 11.5% in North America and 33.9% in United Kingdom.
[6]
(5) 83.1% of fair value shown is domiciled in Europe and 16.9% in North America.
[7]
(9) This investment is measured at fair value using the net asset value practical expedient under Accounting Standards Codification 820, Fair Value Measurement (“ASC 820”).
[8]
(8) This investment is measured at fair value using the net asset value practical expedient under ASC 820.
[9]
(6) 67.1% of fair value shown is domiciled in Europe, 2.0% in North America and 30.9% in United Kingdom.
[10]
(6) 69.4% of fair value shown is domiciled in Europe, 2.1% in North America and 28.5% in United Kingdom.
[11]
(7) 1.2% of fair value shown is domiciled in Asia Pacific, 35.3% in Europe and 63.5% in North America.
[12]
(7) 33.5% of fair value shown is domiciled in North America, 30.9% in Asia Pacific, 11.1% in United Kingdom, and 24.5% in Europe.
[13]
(8) 25.2% of fair value shown is domiciled in Asia Pacific, 35.3% in Europe, 23.9% in North America and 15.6% in United Kingdom.
[14]
(3) The aggregator that holds Smart Metering Systems Limited also holds indirect interests in Salisbury Topco Limited and SMA Topco Limited.
[15]
(3) The aggregator that holds Smart Metering Systems Limited also holds indirect interests in Salisbury Topco Limited and SMA Topco Limited.