Investments and Fair Value Measurement - Summary of Financial Information of Unconsolidated Significant Investments (Detail) - BXINFRA Aggregator (CYM) L.P. [Member] - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
Assets
Cash and Cash Equivalents	$ 64,744
Investments	3,239,592
Investee Funds	920,479	$ 0
Derivative Assets	143	$ 0
Total Assets	4,224,958
Liabilities, Fair Value Disclosure [Abstract]
Derivative Liabilities	265
Debt Investments [Member]
Assets
Investments	1,166,894
Debt Investments [Member] \| Infrastructure Debt Investment [Member]
Assets
Investments	698,531
Debt Investments [Member] \| Liquid Debt Investment [Member]
Assets
Investments	468,363
Equity Investments [Member]
Assets
Investments	2,072,698
Level I [Member]
Assets
Cash and Cash Equivalents	64,744
Investments	0
Investee Funds	18,866
Derivative Assets	0
Total Assets	83,610
Liabilities, Fair Value Disclosure [Abstract]
Derivative Liabilities	0
Level I [Member] \| Debt Investments [Member]
Assets
Investments	0
Level I [Member] \| Debt Investments [Member] \| Infrastructure Debt Investment [Member]
Assets
Investments	0
Level I [Member] \| Debt Investments [Member] \| Liquid Debt Investment [Member]
Assets
Investments	0
Level I [Member] \| Equity Investments [Member]
Assets
Investments	0
Level II [Member]
Assets
Cash and Cash Equivalents	0
Investments	991,006
Investee Funds	55,268
Derivative Assets	143
Total Assets	1,046,417
Liabilities, Fair Value Disclosure [Abstract]
Derivative Liabilities	265
Level II [Member] \| Debt Investments [Member]
Assets
Investments	959,721
Level II [Member] \| Debt Investments [Member] \| Infrastructure Debt Investment [Member]
Assets
Investments	491,358
Level II [Member] \| Debt Investments [Member] \| Liquid Debt Investment [Member]
Assets
Investments	468,363
Level II [Member] \| Equity Investments [Member]
Assets
Investments	31,285
Level III [Member]
Assets
Cash and Cash Equivalents	0
Investments	2,248,586
Investee Funds	776,568
Derivative Assets	0
Total Assets	3,025,154
Liabilities, Fair Value Disclosure [Abstract]
Derivative Liabilities	0
Level III [Member] \| Debt Investments [Member]
Assets
Investments	207,173
Level III [Member] \| Debt Investments [Member] \| Infrastructure Debt Investment [Member]
Assets
Investments	207,173
Level III [Member] \| Debt Investments [Member] \| Liquid Debt Investment [Member]
Assets
Investments	0
Level III [Member] \| Equity Investments [Member]
Assets
Investments	2,041,413
NAV [Member]
Assets
Cash and Cash Equivalents	0
Investments	0
Investee Funds	69,777
Derivative Assets	0
Total Assets	69,777
Liabilities, Fair Value Disclosure [Abstract]
Derivative Liabilities	0
NAV [Member] \| Debt Investments [Member]
Assets
Investments	0
NAV [Member] \| Debt Investments [Member] \| Infrastructure Debt Investment [Member]
Assets
Investments	0
NAV [Member] \| Debt Investments [Member] \| Liquid Debt Investment [Member]
Assets
Investments	0
NAV [Member] \| Equity Investments [Member]
Assets
Investments	$ 0

Fair value portion of asset recognized for present right to economic benefit.

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Fair value of financial and nonfinancial obligations.

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