Revenue - Summary of Investment Advisory, Administration Fees and Securities Lending Revenue by Type (Detail) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2025	Mar. 31, 2024
Disaggregation Of Revenue [Line Items]
Total revenue		$ 5,276	$ 4,728
Investment Advisory, Administration Fees and Securities Lending Revenue [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	[1],[2]	4,401	3,778
Investment Advisory, Administration Fees and Securities Lending Revenue [Member] | Equity Active Product [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	[2]	518	516
Investment Advisory, Administration Fees and Securities Lending Revenue [Member] | Equity ETFs [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	[2]	1,349	1,190
Investment Advisory, Administration Fees and Securities Lending Revenue [Member] | Equity [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	[2]	1,867	1,706
Investment Advisory, Administration Fees and Securities Lending Revenue [Member] | Fixed Income Active [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	[2]	492	484
Investment Advisory, Administration Fees and Securities Lending Revenue [Member] | Fixed Income ETFs [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	[2]	352	327
Investment Advisory, Administration Fees and Securities Lending Revenue [Member] | Fixed Income [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	[2]	844	811
Investment Advisory, Administration Fees and Securities Lending Revenue [Member] | Active Multi-Asset [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	[2]	313	305
Investment Advisory, Administration Fees and Securities Lending Revenue [Member] | Alternatives [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	[2]	685	378
Investment Advisory, Administration Fees and Securities Lending Revenue [Member] | Alternatives [Member] | Liquid Alternatives [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	[2]	150	138
Investment Advisory, Administration Fees and Securities Lending Revenue [Member] | Alternatives [Member] | Private Markets [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	[2]	535	240
Investment Advisory, Administration Fees and Securities Lending Revenue [Member] | Non-ETF Index [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	[2]	307	288
Investment Advisory, Administration Fees and Securities Lending Revenue [Member] | Digital Assets, Commodities and Multi-asset ETFs [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	[2],[3]	92	45
Investment Advisory, Administration Fees and Securities Lending Revenue [Member] | Cash Management [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	[2]	293	245
Investment Advisory, Administration Fees and Securities Lending Revenue [Member] | Long-term [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	[2]	4,108	3,533
Investment Advisory Performance Fees [Member]
Disaggregation Of Revenue [Line Items]
Total revenue		60	204
Investment Advisory Performance Fees [Member] | Equity [Member]
Disaggregation Of Revenue [Line Items]
Total revenue		10	8
Investment Advisory Performance Fees [Member] | Fixed Income [Member]
Disaggregation Of Revenue [Line Items]
Total revenue		12	4
Investment Advisory Performance Fees [Member] | Multi-asset [Member]
Disaggregation Of Revenue [Line Items]
Total revenue		4	2
Investment Advisory Performance Fees [Member] | Alternatives [Member]
Disaggregation Of Revenue [Line Items]
Total revenue		34	190
Investment Advisory Performance Fees [Member] | Alternatives [Member] | Liquid Alternatives [Member]
Disaggregation Of Revenue [Line Items]
Total revenue		10	65
Investment Advisory Performance Fees [Member] | Alternatives [Member] | Private Markets [Member]
Disaggregation Of Revenue [Line Items]
Total revenue		24	125
Technology Services and Subscription Revenue [Member]
Disaggregation Of Revenue [Line Items]
Total revenue		436	377
Distribution Fees [Member]
Disaggregation Of Revenue [Line Items]
Total revenue		321	310
Advisory and Other Revenue [Member]
Disaggregation Of Revenue [Line Items]
Total revenue		58	59
Advisory and Other Revenue [Member] | Advisory [Member]
Disaggregation Of Revenue [Line Items]
Total revenue		14	13
Advisory and Other Revenue [Member] | Other [Member]
Disaggregation Of Revenue [Line Items]
Total revenue		$ 44	$ 46

[1] Amounts include $157 million and $151 million of securities lending revenue for the three months ended March 31, 2025 and 2024, respectively.

[2] Beginning in the first quarter of 2025, BlackRock reclassified the presentation of the Company's investment advisory, administration fees and securities lending revenue line items to align with the updated presentation of the Company's AUM line items. Such line items have been reclassified for 2024 to conform to this new presentation. See page 11 of Exhibit 99.2 to the Current Report on Form 8-K furnished on April 11, 2025 for the reclassified presentation of the 2024 investment advisory, administration fees and securities lending revenue line items.

[3] Amounts include commodity ETFs and exchange-traded products ("ETPs").