v3.26.1
Financial Highlights - Schedule of Financial Highlights (Details) - ISQ Open Infrastructure Company LLC - Series II [Member] - USD ($)
 6 Months Ended
Jun. 30, 2026
Mar. 31, 2026
Dec. 31, 2025
Jun. 30, 2025
Mar. 31, 2025
Mar. 27, 2025
F-STE Shares [Member]            
Per Share Data:            
Net asset value at beginning of period $ 30.54          
Proceeds from issuance of shares          
Premium/(Discount) on issuance of shares 2.23          
Distributions declared [1] (0.83)          
Service fees (1.55)          
Net investment income/(loss) [2] (0.26)          
Net realized and unrealized gain/(loss) [3] 1.3          
Reallocation of unrealized gain/(loss) 0.48          
Net increase/(decrease) in net assets resulting from operations 1.52          
Net asset value at end of period $ 31.91          
Shares outstanding at end of period (in Shares) 1,191,472 503,216 105,792
Weighted average shares outstanding (in Shares) 745,285          
Ratio/Supplemental Data:            
Net assets at end of period (in Dollars) $ 38,018,838   $ 3,231,299      
Total expenses before expense support and after performance participation allocation [4],[5] 7.41%          
Total expenses after expense support and after performance participation allocation [4],[5] 3.97%          
Total expenses after expense support and before performance participation allocation [4],[5] 3.61%          
Net investment loss [5] (1.65%)          
Total return [6],[7] 7.20%          
F-DTE Shares [Member]            
Per Share Data:            
Net asset value at beginning of period $ 32.19          
Proceeds from issuance of shares          
Premium/(Discount) on issuance of shares 0          
Distributions declared [1] (0.84)          
Service fees 0.01          
Net investment income/(loss) [2] (0.61)          
Net realized and unrealized gain/(loss) [3] 1.63          
Reallocation of unrealized gain/(loss) (0.79)          
Net increase/(decrease) in net assets resulting from operations 0.23          
Net asset value at end of period $ 31.59          
Shares outstanding at end of period (in Shares) 405,755 401,494 400,100
Weighted average shares outstanding (in Shares) 402,691          
Ratio/Supplemental Data:            
Net assets at end of period (in Dollars) $ 12,817,846   $ 12,878,001      
Total expenses before expense support and after performance participation allocation [4],[5] 9.82%          
Total expenses after expense support and after performance participation allocation [4],[5] 6.34%          
Total expenses after expense support and before performance participation allocation [4],[5] 3.45%          
Net investment loss [5] (3.86%)          
Total return [6],[7] 0.76%          
F-ITE Shares [Member]            
Per Share Data:            
Net asset value at beginning of period $ 32.44          
Proceeds from issuance of shares          
Premium/(Discount) on issuance of shares (0.14)          
Distributions declared [1] (0.89)          
Service fees          
Net investment income/(loss) [2] (0.14)          
Net realized and unrealized gain/(loss) [3] 1.31          
Reallocation of unrealized gain/(loss) (0.04)          
Net increase/(decrease) in net assets resulting from operations 1.13          
Net asset value at end of period $ 32.54          
Shares outstanding at end of period (in Shares) 152,528 71,385 40,677
Weighted average shares outstanding (in Shares) 88,699          
Ratio/Supplemental Data:            
Net assets at end of period (in Dollars) $ 4,963,116   $ 1,319,688      
Total expenses before expense support and after performance participation allocation [4],[5] 6.89%          
Total expenses after expense support and after performance participation allocation [4],[5] 3.38%          
Total expenses after expense support and before performance participation allocation [4],[5] 3.29%          
Net investment loss [5] (0.88%)          
Total return [6],[7] 3.06%          
F-JTE Shares [Member]            
Per Share Data:            
Net asset value at beginning of period $ 31.73          
Proceeds from issuance of shares          
Premium/(Discount) on issuance of shares 0.04          
Distributions declared [1] (0.84)          
Service fees (0.1)          
Net investment income/(loss) [2] (0.55)          
Net realized and unrealized gain/(loss) [3] 1.6          
Reallocation of unrealized gain/(loss) (0.13)          
Net increase/(decrease) in net assets resulting from operations 0.92          
Net asset value at end of period $ 31.75          
Shares outstanding at end of period (in Shares) 738,981 698,805 572,307
Weighted average shares outstanding (in Shares) 699,793          
Ratio/Supplemental Data:            
Net assets at end of period (in Dollars) $ 23,462,815   $ 18,158,680      
Total expenses before expense support and after performance participation allocation [4],[5] 9.48%          
Total expenses after expense support and after performance participation allocation [4],[5] 5.96%          
Total expenses after expense support and before performance participation allocation [4],[5] 3.61%          
Net investment loss [5] (3.50%)          
Total return [6],[7] 2.72%          
STE Shares [Member]            
Per Share Data:            
Net asset value at beginning of period $ 31.36          
Proceeds from issuance of shares          
Premium/(Discount) on issuance of shares (0.08)          
Distributions declared [1] (0.84)          
Service fees 0.07          
Net investment income/(loss) [2] (0.74)          
Net realized and unrealized gain/(loss) [3] 1.63          
Reallocation of unrealized gain/(loss) (0.8)          
Net increase/(decrease) in net assets resulting from operations 0.09          
Net asset value at end of period $ 30.6          
Shares outstanding at end of period (in Shares) 100 100 100
Weighted average shares outstanding (in Shares) 100          
Ratio/Supplemental Data:            
Net assets at end of period (in Dollars) $ 3,060   $ 3,136      
Total expenses before expense support and after performance participation allocation [4],[5] 10.98%          
Total expenses after expense support and after performance participation allocation [4],[5] 7.43%          
Total expenses after expense support and before performance participation allocation [4],[5] 4.47%          
Net investment loss [5] (4.86%)          
Total return [6],[7] 0.26%          
DTE Shares [Member]            
Per Share Data:            
Net asset value at beginning of period $ 32.12          
Proceeds from issuance of shares          
Premium/(Discount) on issuance of shares (0.09)          
Distributions declared [1] (0.84)          
Service fees 0.02          
Net investment income/(loss) [2] (0.68)          
Net realized and unrealized gain/(loss) [3] 1.63          
Reallocation of unrealized gain/(loss) (0.8)          
Net increase/(decrease) in net assets resulting from operations 0.15          
Net asset value at end of period $ 31.36          
Shares outstanding at end of period (in Shares) 100 100 100
Weighted average shares outstanding (in Shares) 100          
Ratio/Supplemental Data:            
Net assets at end of period (in Dollars) $ 3,136   $ 3,212      
Total expenses before expense support and after performance participation allocation [4],[5] 10.31%          
Total expenses after expense support and after performance participation allocation [4],[5] 6.85%          
Total expenses after expense support and before performance participation allocation [4],[5] 3.97%          
Net investment loss [5] (4.36%)          
Total return [6],[7] 0.26%          
ITE Shares [Member]            
Per Share Data:            
Net asset value at beginning of period $ 32.43          
Proceeds from issuance of shares          
Premium/(Discount) on issuance of shares (0.09)          
Distributions declared [1] (0.84)          
Service fees          
Net investment income/(loss) [2] (0.66)          
Net realized and unrealized gain/(loss) [3] 1.64          
Reallocation of unrealized gain/(loss) (0.8)          
Net increase/(decrease) in net assets resulting from operations 0.18          
Net asset value at end of period $ 31.68          
Shares outstanding at end of period (in Shares) 100 100 100
Weighted average shares outstanding (in Shares) 100          
Ratio/Supplemental Data:            
Net assets at end of period (in Dollars) $ 3,168   $ 3,243      
Total expenses before expense support and after performance participation allocation [4],[5] 10.08%          
Total expenses after expense support and after performance participation allocation [4],[5] 6.65%          
Total expenses after expense support and before performance participation allocation [4],[5] 3.80%          
Net investment loss [5] (4.18%)          
Total return [6],[7] 0.29%          
JTE Shares [Member]            
Per Share Data:            
Net asset value at beginning of period $ 31.8          
Proceeds from issuance of shares          
Premium/(Discount) on issuance of shares 3.31          
Distributions declared [1] (0.79)          
Service fees (3.01)          
Net investment income/(loss) [2] (0.29)          
Net realized and unrealized gain/(loss) [3] 0.34          
Reallocation of unrealized gain/(loss)          
Net increase/(decrease) in net assets resulting from operations 0.05          
Net asset value at end of period $ 31.36          
Shares outstanding at end of period (in Shares) 86,651 100 100
Weighted average shares outstanding (in Shares) 17,917          
Ratio/Supplemental Data:            
Net assets at end of period (in Dollars) $ 2,717,390   $ 3,180      
Total expenses before expense support and after performance participation allocation [4],[5] 9.42%          
Total expenses after expense support and after performance participation allocation [4],[5] 5.55%          
Total expenses after expense support and before performance participation allocation [4],[5] 4.12%          
Net investment loss [5] (1.85%)          
Total return [6],[7] 1.11%          
ETE Shares [Member]            
Per Share Data:            
Net asset value at beginning of period $ 33.6          
Proceeds from issuance of shares          
Premium/(Discount) on issuance of shares (0.72)          
Distributions declared [1] (0.84)          
Service fees          
Net investment income/(loss) [2]          
Net realized and unrealized gain/(loss) [3] 1.66          
Reallocation of unrealized gain/(loss) (0.77)          
Net increase/(decrease) in net assets resulting from operations 0.89          
Net asset value at end of period $ 32.93          
Shares outstanding at end of period (in Shares) 41 40 40 40 40
Weighted average shares outstanding (in Shares) 40          
Ratio/Supplemental Data:            
Net assets at end of period (in Dollars) $ 1,350   $ 1,344      
Total expenses before expense support and after performance participation allocation [4],[5] 5.85%          
Total expenses after expense support and after performance participation allocation [4],[5] 2.40%          
Total expenses after expense support and before performance participation allocation [4],[5] 2.40%          
Net investment loss [5] 0.00%          
Total return [6],[7] 0.52%          
F-S Shares [Member]            
Per Share Data:            
Net asset value at beginning of period $ 30.12          
Proceeds from issuance of shares          
Premium/(Discount) on issuance of shares 1.86          
Distributions declared [1] (0.79)          
Service fees (1.48)          
Net investment income/(loss) [2] (0.16)          
Net realized and unrealized gain/(loss) [3] 1.25          
Reallocation of unrealized gain/(loss) 0.3          
Net increase/(decrease) in net assets resulting from operations 1.39          
Net asset value at end of period $ 31.1          
Shares outstanding at end of period (in Shares) 2,036,534 759,798 448,694
Weighted average shares outstanding (in Shares) 1,103,699          
Ratio/Supplemental Data:            
Net assets at end of period (in Dollars) $ 63,342,664   $ 13,513,460      
Total expenses before expense support and after performance participation allocation [4],[5] 7.14%          
Total expenses after expense support and after performance participation allocation [4],[5] 3.59%          
Total expenses after expense support and before performance participation allocation [4],[5] 3.67%          
Net investment loss [5] (1.01%)          
Total return [6],[7] 5.88%          
F-I Shares [Member]            
Per Share Data:            
Net asset value at beginning of period $ 32.07          
Proceeds from issuance of shares          
Premium/(Discount) on issuance of shares (0.16)          
Distributions declared [1] (0.79)          
Service fees          
Net investment income/(loss) [2] (0.16)          
Net realized and unrealized gain/(loss) [3] 1.3          
Reallocation of unrealized gain/(loss)          
Net increase/(decrease) in net assets resulting from operations 1.14          
Net asset value at end of period $ 32.26          
Shares outstanding at end of period (in Shares) 834,780 400,558 207,668
Weighted average shares outstanding (in Shares) 543,936          
Ratio/Supplemental Data:            
Net assets at end of period (in Dollars) $ 26,926,148   $ 6,660,049      
Total expenses before expense support and after performance participation allocation [4],[5] 6.67%          
Total expenses after expense support and after performance participation allocation [4],[5] 3.30%          
Total expenses after expense support and before performance participation allocation [4],[5] 3.23%          
Net investment loss [5] (1.01%)          
Total return [6],[7] 3.06%          
F-J Shares [Member]            
Per Share Data:            
Net asset value at beginning of period $ 31.33          
Proceeds from issuance of shares          
Premium/(Discount) on issuance of shares (0.01)          
Distributions declared [1] (0.79)          
Service fees (0.18)          
Net investment income/(loss) [2] (0.48)          
Net realized and unrealized gain/(loss) [3] 1.55          
Reallocation of unrealized gain/(loss) (0.01)          
Net increase/(decrease) in net assets resulting from operations 1.06          
Net asset value at end of period $ 31.41          
Shares outstanding at end of period (in Shares) 4,252,997 3,970,498 2,862,789
Weighted average shares outstanding (in Shares) 3,952,424          
Ratio/Supplemental Data:            
Net assets at end of period (in Dollars) $ 133,569,315   $ 89,697,782      
Total expenses before expense support and after performance participation allocation [4],[5] 9.06%          
Total expenses after expense support and after performance participation allocation [4],[5] 5.56%          
Total expenses after expense support and before performance participation allocation [4],[5] 3.56%          
Net investment loss [5] (3.10%)          
Total return [6],[7] 2.78%          
I Shares [Member]            
Per Share Data:            
Net asset value at beginning of period [6]          
Proceeds from issuance of shares [6] 25          
Premium/(Discount) on issuance of shares [6] (0.06)          
Distributions declared [1],[6] (0.34)          
Service fees [6]          
Net investment income/(loss) [2],[6]          
Net realized and unrealized gain/(loss) [3],[6] 0.07          
Reallocation of unrealized gain/(loss) [6]          
Net increase/(decrease) in net assets resulting from operations [6] 0.07          
Net asset value at end of period [6] $ 24.67          
Shares outstanding at end of period (in Shares) 13,000 [6]      
Weighted average shares outstanding (in Shares) [6] 2,155          
Ratio/Supplemental Data:            
Net assets at end of period (in Dollars) [6] $ 320,702          
Total expenses before expense support and after performance participation allocation [4],[5],[6] 8.62%          
Total expenses after expense support and after performance participation allocation [4],[5],[6] 4.23%          
Total expenses after expense support and before performance participation allocation [4],[5],[6] 4.23%          
Net investment loss [5],[6] 0.03%          
Total return [6],[7] 0.05%          
J Shares [Member]            
Per Share Data:            
Net asset value at beginning of period [6]          
Proceeds from issuance of shares [6] 25          
Premium/(Discount) on issuance of shares [6] 1.34          
Distributions declared [1],[6] (0.34)          
Service fees [6] (1.99)          
Net investment income/(loss) [2],[6] (0.09)          
Net realized and unrealized gain/(loss) [3],[6] 0.38          
Reallocation of unrealized gain/(loss) [6]          
Net increase/(decrease) in net assets resulting from operations [6] 0.29          
Net asset value at end of period [6] $ 24.3          
Shares outstanding at end of period (in Shares) 187,442 [6]      
Weighted average shares outstanding (in Shares) [6] 45,535          
Ratio/Supplemental Data:            
Net assets at end of period (in Dollars) [6] $ 4,555,475          
Total expenses before expense support and after performance participation allocation [4],[5],[6] 7.49%          
Total expenses after expense support and after performance participation allocation [4],[5],[6] 4.00%          
Total expenses after expense support and before performance participation allocation [4],[5],[6] 4.00%          
Net investment loss [5],[6] (0.70%)          
Total return [6],[7] (1.43%)          
E Shares [Member]            
Per Share Data:            
Net asset value at beginning of period $ 33.57          
Proceeds from issuance of shares          
Premium/(Discount) on issuance of shares (0.13)          
Distributions declared [1] (0.79)          
Service fees          
Net investment income/(loss) [2] (0.01)          
Net realized and unrealized gain/(loss) [3] 1.63          
Reallocation of unrealized gain/(loss) (0.58)          
Net increase/(decrease) in net assets resulting from operations 1.04          
Net asset value at end of period $ 33.69          
Shares outstanding at end of period (in Shares) 466,420 453,080 377,933
Weighted average shares outstanding (in Shares) 440,904          
Ratio/Supplemental Data:            
Net assets at end of period (in Dollars) $ 15,715,715   $ 12,685,360      
Total expenses before expense support and after performance participation allocation [4],[5] 5.92%          
Total expenses after expense support and after performance participation allocation [4],[5] 2.49%          
Total expenses after expense support and before performance participation allocation [4],[5] 2.49%          
Net investment loss [5] (0.08%)          
Total return [6],[7] 2.72%          
[1] The per share data for distributions was derived by using the actual shares outstanding at the date of the relevant transaction (refer to Note 8).
[2] The per share data was derived by using the weighted average shares outstanding during the applicable period.
[3] The amount shown at this caption is the balancing amount derived from the other figures in the table. The amount shown at this caption for a share outstanding throughout the period may not agree with the change in the aggregate gains and losses in investments for the period because of the timing of sales of Series II shares in relation to fluctuating market value for the portfolio.
[4] Actual results may not be indicative of future results. Additionally, an individual shareholder's ratio may vary from the ratios presented for a share class as a whole.
[5] The ratios were derived using the simple average net assets during the applicable period.
[6] Class I shares and Class J shares were first issued on June 1, 2026 and May 1, 2026, respectively. Amounts presented are for the period from issuance date through June 30, 2026. The ratios of expense and net investment income (loss) and the total return for these share classes have not been annualized.
[7] The total return is calculated for each share class as the change in the net asset value for such share class during the period plus any distributions per share declared in the period. Amounts are not representative of total return as calculated for purposes of the Performance Participation Allocation as described in Note 6. The Series II performance changes over time and currently may be different than that shown above. Past performance is no guarantee of future results. Investment performance is presented without regard to sales load that may be incurred by Shareholders in the purchase of the Series II shares.