Net Assets - Summary of the Units issued during the period (Detail) - shares	6 Months Ended	12 Months Ended
Dec. 31, 2024	Dec. 31, 2025
Net Assets [Line Items]
Beginning Units Outstanding	0	4,000
Units Issued	4,000	128,191,228
Distribution Reinvested		1,210,782
Conversion of Units Between Classes		(1,730)
Redemption of Units		(32,452)
Ending Units Outstanding	4,000	129,371,828
Class I Units [Member]
Net Assets [Line Items]
Beginning Units Outstanding	0	4,000
Units Issued	4,000	82,384,367
Distribution Reinvested		678,766
Conversion of Units Between Classes		90,541
Redemption of Units		(19,571)
Ending Units Outstanding	4,000	83,138,103
Class S Units [Member]
Net Assets [Line Items]
Beginning Units Outstanding	0	0
Units Issued	0	41,953,559
Distribution Reinvested		484,058
Conversion of Units Between Classes		(462,693)
Redemption of Units		(12,881)
Ending Units Outstanding	0	41,962,043
Class D Units [Member]
Net Assets [Line Items]
Beginning Units Outstanding	0	0
Units Issued	0	3,853,302
Distribution Reinvested		47,958
Conversion of Units Between Classes		370,422
Redemption of Units		0
Ending Units Outstanding	0	4,271,682
BXINFRA Aggregator (CYM) L.P. [Member]
Net Assets [Line Items]
Beginning Units Outstanding		0
Units Issued		137,387,610
Distribution Reinvested		1,232,937
Redemption of Units		(69,256)
Ending Units Outstanding	0	138,551,291
BXINFRA Aggregator (CYM) L.P. [Member] \| Class A Units [Member]
Net Assets [Line Items]
Beginning Units Outstanding		0
Units Issued		137,387,610
Distribution Reinvested		1,232,937
Redemption of Units		(69,256)
Ending Units Outstanding	0	138,551,291

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- Definition

The number of limited partner units outstanding.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Section S99
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- Definition

The number of shares issued during the period upon the conversion of units. An example of a convertible unit is an umbrella partnership real estate investment trust unit (UPREIT unit).

+ References

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- Definition

Number of shares issued during the period from a dividend reinvestment plan (DRIP). A dividend reinvestment plan allows the shareholders to reinvest dividends paid to them by the entity on new issues of stock by the entity.

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- Definition

Number of new stock issued during the period.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Number of stock bought back by the entity at the exercise price or redemption price.

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