Significant Accounting Policies (Policies)	6 Months Ended
Jun. 30, 2024
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation These condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States (“GAAP”) and include the accounts of the Company and its controlled subsidiaries. Noncontrolling interests (“NCI”) on the condensed consolidated statements of financial condition represent the portion of consolidated sponsored investment products (“CIPs”) and a consolidated affiliate in which the Company does not have direct equity ownership. Intercompany balances and transactions have been eliminated upon consolidation. The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenue and expense during the reporting periods. Actual results could differ from those estimates. Certain financial information that normally is included in annual financial statements, including certain financial statement footnotes, is not required for interim reporting purposes and has been condensed or omitted herein. These condensed consolidated financial statements should be read in conjunction with the Company’s consolidated financial statements and footnotes related thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2023, which was filed with the Securities and Exchange Commission (“SEC”) on February 23, 2024 (“2023 Form 10-K”). The interim financial information at June 30, 2024 and for the three and six months ended June 30, 2024 and 2023 is unaudited. However, in the opinion of management, the interim information includes all normal recurring adjustments necessary for the fair presentation of the Company’s results for the periods presented. The results of operations for interim periods are not necessarily indicative of results to be expected for the full year. Certain prior period presentations were reclassified to ensure comparability with current period classifications.
Accounting Developments	Accounting Developments Segment Reporting. In November 2023, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2023-07, Improvements to Reportable Segment Disclosures (“ASU 2023-07”), which requires incremental disclosures about reportable segments but does not change the definition of a segment or the guidance for determining reportable segments. The new guidance requires disclosure of significant segment expenses that are (1) regularly provided to (or easily computed from information regularly provided to) the chief operating decision maker ("CODM") and (2) included in the reported measure of segment profit or loss. The new standard also requires companies to disclose the title and position of the individual (or the name of the committee) identified as the CODM, allows companies to disclose multiple measures of segment profit or loss if those measures are used to assess performance and allocate resources, and is applicable to companies with a single reportable segment. The requirements are effective for annual reporting periods beginning on January 1, 2024, and are required to be applied retrospectively. Early adoption is permitted. The Company does not expect the additional disclosure requirements under ASU 2023-07 to have a material impact on the consolidated financial statements. Income Tax Disclosure Requirements. In December 2023, the FASB issued ASU 2023-09, Improvements to Income Tax Disclosures (“ASU 2023-09”), which enhances interim and annual income tax disclosures. The two primary enhancements disaggregate existing income tax disclosures related to the effective tax rate reconciliation and income taxes paid. The additional disclosure requirements under ASU 2023-09 are required to be applied prospectively and are effective for the Company on January 1, 2025. The Company does not expect the additional disclosure requirements under ASU 2023-09 to have a material impact on the consolidated financial statements.
Fair Value Measurements	Fair Value Measurements Hierarchy of Fair Value Inputs. The Company uses a fair value hierarchy that prioritizes inputs to valuation approaches used to measure fair value. The fair value hierarchy gives the highest priority to quoted prices (unadjusted) in active markets for identical assets or liabilities and the lowest priority to unobservable inputs. Assets and liabilities measured and reported at fair value are classified and disclosed in one of the following categories: Level 1 Inputs: Quoted prices (unadjusted) in active markets for identical assets or liabilities at the reporting date. • Level 1 assets may include listed mutual funds, ETFs, listed equities, commodities and certain exchange-traded derivatives. Level 2 Inputs: Quoted prices for similar assets or liabilities in active markets; quoted prices for identical or similar assets or liabilities that are not active; quotes from pricing services or brokers for which the Company can determine that orderly transactions took place at the quoted price or that the inputs used to arrive at the price are observable; and inputs other than quoted prices that are observable, such as models or other valuation methodologies. • Level 2 assets may include debt securities, loans held within consolidated collateralized loan obligations (“CLOs”), short-term floating-rate notes, asset-backed securities, as well as over-the-counter derivatives, including interest rate swaps and foreign currency exchange contracts that have inputs to the valuations that generally can be corroborated by observable market data. Level 3 Inputs: Unobservable inputs for the valuation of the asset or liability, which may include nonbinding broker quotes. Level 3 assets include investments for which there is little, if any, market activity. These inputs require significant management judgment or estimation. • Level 3 assets may include direct private equity investments, including those held within CIPs, investments in CLOs, and loans held within consolidated CLOs and CIPs. • Level 3 liabilities may include borrowings of consolidated CLOs and contingent liabilities related to acquisitions valued based upon discounted cash flow analyses, using unobservable market data, or other valuation techniques. Significance of Inputs. The Company’s assessment of the significance of a particular input to the fair value measurement in its entirety requires judgment and considers factors specific to the financial instrument. Valuation Approaches. The fair values of certain Level 3 assets and liabilities were determined using various valuation approaches as appropriate, including third-party pricing vendors, broker quotes and market and income approaches. A significant number of inputs used to value equity, debt securities, and loans held within CLOs and CIPs are sourced from third-party pricing vendors. Generally, prices obtained from pricing vendors are categorized as Level 1 inputs for identical securities traded in active markets and as Level 2 for other similar securities if the vendor uses observable inputs in determining the price. In addition, quotes obtained from brokers generally are nonbinding and categorized as Level 3 inputs. However, if the Company is able to determine that market participants have transacted for the asset in an orderly manner near the quoted price or if the Company can determine that the inputs used by the broker are observable, the quote is classified as a Level 2 input. Investments Measured at Net Asset Value. As a practical expedient, the Company uses net asset value (“NAV”) as the fair value for certain investments. The inputs to value these investments may include the Company’s capital accounts for its partnership interests in various alternative investments, including hedge funds, real assets and private equity funds, which may be adjusted by using the returns of certain market indices. The various partnerships are investment companies, which record their underlying investments at fair value based on fair value policies established by management of the underlying fund. Fair value policies at the underlying fund generally require the fund to utilize pricing/valuation information from third-party sources, including independent appraisals. However, in some instances, current valuation information for illiquid securities or securities in markets that are not active may not be available from any third-party source or fund management may conclude that the valuations that are available from third-party sources are not reliable. In these instances, fund management may perform model-based analytical valuations that could be used as an input to value these investments. Fair Value Assets and Liabilities of Consolidated CLO. The Company applies the fair value option provisions for eligible assets, including loans, held by a consolidated CLO. As the fair value of the financial assets of the consolidated CLO is more observable than the fair value of the borrowings of the consolidated CLO, the Company measures the fair value of the borrowings of the consolidated CLO equal to the fair value of the assets of the consolidated CLO less the fair value of the Company’s economic interest in the CLO.
Derivatives and Hedging Activities	Derivatives and Hedging Activities. The Company does not use derivative financial instruments for trading or speculative purposes. The Company uses derivative financial instruments primarily for purposes of hedging exposures to fluctuations in foreign currency exchange rates of certain assets and liabilities, and market price and interest rate exposures with respect to its total portfolio of seed investments in sponsored investment products. Certain CIPs also utilize derivatives as a part of their investment strategies. In addition, the Company uses derivatives and makes investments to economically hedge market valuation changes on certain deferred cash compensation plans, for which the final value of the deferred amount distributed to employees in cash upon vesting is determined based on the returns of specified investment funds. The Company recognizes compensation expense for the appreciation (depreciation) of the deferred cash compensation liability in proportion to the vested amount of the award during a respective period, while the gain (loss) to economically hedge these plans is immediately recognized in nonoperating income (expense). See Note 4, Investments, and Note 8, Derivatives and Hedging, for further information on the Company’s investments and derivatives, respectively, used to economically hedge these deferred cash compensation plans. The Company records all derivative financial instruments as either assets or liabilities at fair value on a gross basis in the condensed consolidated statements of financial condition. Credit risks are managed through master netting and collateral support agreements. The amounts related to the right to reclaim or the obligation to return cash collateral may not be used to offset amounts due under the derivative instruments in the normal course of settlement. Therefore, such amounts are not offset against fair value amounts recognized for derivative instruments with the same counterparty and are included in other assets and other liabilities. Changes in the fair value of the Company’s derivative financial instruments are recognized in earnings and, where applicable, are offset by the corresponding gain or loss on the related foreign-denominated or hedged assets or liabilities, on the condensed consolidated statements of income. The Company may also use financial instruments designated as net investment hedges for accounting purposes to hedge net investments in international subsidiaries, the functional currency of which is not United States ("US") dollars. The gain or loss from revaluing net investment hedges at the spot rate is deferred and reported within accumulated other comprehensive income (loss) (“AOCI”) on the condensed consolidated statements of financial condition. The Company reassesses the effectiveness of its net investment hedge at least quarterly.
Separate Account Assets and Liabilities	Separate Account Assets and Liabilities. Separate account assets are maintained by BlackRock Life Limited, a wholly owned subsidiary of the Company, which is a registered life insurance company in the United Kingdom (“UK”), and represent segregated assets held for purposes of funding individual and group pension contracts. The life insurance company does not underwrite any insurance contracts that involve any insurance risk transfer from the insured to the life insurance company. The separate account assets primarily include equity securities, debt securities, money market funds and derivatives. The separate account assets are not subject to general claims of the creditors of BlackRock. These separate account assets and the related equal and offsetting liabilities are recorded as separate account assets and separate account liabilities on the condensed consolidated statements of financial condition. The net investment income attributable to separate account assets supporting individual and group pension contracts accrues directly to the contract owner and is not reported on the condensed consolidated statements of income. While BlackRock has no economic interest in these separate account assets and liabilities, BlackRock earns policy administration and management fees associated with these products, which are included in investment advisory, administration fees and securities lending revenue on the condensed consolidated statements of income.
Separate Account Collateral Assets Held and Liabilities Under Securities Lending Agreements	Separate Account Collateral Assets Held and Liabilities Under Securities Lending Agreements. The Company facilitates securities lending arrangements whereby securities held by separate accounts maintained by BlackRock Life Limited are lent to third parties under global master securities lending agreements. In exchange, the Company obtains either (1) the legal title, or (2) a first ranking priority security interest, in the collateral. The minimum collateral values generally range from approximately 102% to 112% of the value of the securities in order to reduce counterparty risk. The required collateral value is calculated on a daily basis. The global master securities lending agreements provide the Company the right to request additional collateral or, in the event of borrower default, the right to liquidate collateral. The securities lending transactions entered into by the Company are accompanied by an agreement that entitles the Company to request the borrower to return the securities at any time; therefore, these transactions are not reported as sales. In situations where the Company obtains the legal title to collateral under these securities lending arrangements, the Company records an asset on the condensed consolidated statements of financial condition in addition to an equal collateral liability for the obligation to return the collateral. Additionally, in situations where the Company obtains a first ranking priority security interest in the collateral, the Company does not have the ability to pledge or resell the collateral and therefore does not record the collateral on the condensed consolidated statements of financial condition. At June 30, 2024 and December 31, 2023, the fair value of loaned securities held by separate accounts was approximately $9.5 billion and $9.3 billion, respectively, and the fair value of the collateral under these securities lending agreements was approximately $10.2 billion and $10.1 billion, respectively, of which approximately $5.0 billion as of June 30, 2024 and $4.6 billion as of December 31, 2023 was recognized on the condensed consolidated statements of financial condition. During the six months ended June 30, 2024 and 2023, the Company had not resold or repledged any of the collateral obtained under these arrangements. The securities lending revenue earned from lending securities held by the separate accounts is included in investment advisory, administration fees and securities lending revenue on the condensed consolidated statements of income.

Significant Accounting Policies (Policies)

6 Months Ended

Jun. 30, 2024

These condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States (“GAAP”) and include the accounts of the Company and its controlled subsidiaries. Noncontrolling interests (“NCI”) on the condensed consolidated statements of financial condition represent the portion of consolidated sponsored investment products (“CIPs”) and a consolidated affiliate in which the Company does not have direct equity ownership. Intercompany balances and transactions have been eliminated upon consolidation.

The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenue and expense during the reporting periods. Actual results could differ from those estimates.

Certain financial information that normally is included in annual financial statements, including certain financial statement footnotes, is not required for interim reporting purposes and has been condensed or omitted herein. These condensed consolidated financial statements should be read in conjunction with the Company’s consolidated financial statements and footnotes related thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2023, which was filed with the Securities and Exchange Commission (“SEC”) on February 23, 2024 (“2023 Form 10-K”).

The interim financial information at June 30, 2024 and for the three and six months ended June 30, 2024 and 2023 is unaudited. However, in the opinion of management, the interim information includes all normal recurring adjustments necessary for the fair presentation of the Company’s results for the periods presented. The results of operations for interim periods are not necessarily indicative of results to be expected for the full year.

Certain prior period presentations were reclassified to ensure comparability with current period classifications.

Accounting Developments

Segment Reporting. In November 2023, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2023-07, Improvements to Reportable Segment Disclosures (“ASU 2023-07”), which requires incremental disclosures about reportable segments but does not change the definition of a segment or the guidance for determining reportable segments. The new guidance requires disclosure of significant segment expenses that are (1) regularly provided to (or easily computed from information regularly provided to) the chief operating decision maker ("CODM") and (2) included in the reported measure of segment profit or loss. The new standard also requires companies to disclose the title and position of the individual (or the name of the committee) identified as the CODM, allows companies to disclose multiple measures of segment profit or loss if those measures are used to assess performance and allocate resources, and is applicable to companies with a single reportable segment. The requirements are effective for annual reporting periods beginning on January 1, 2024, and are required to be applied retrospectively. Early adoption is permitted. The Company does not expect the additional disclosure requirements under ASU 2023-07 to have a material impact on the consolidated financial statements.

Income Tax Disclosure Requirements. In December 2023, the FASB issued ASU 2023-09, Improvements to Income Tax Disclosures (“ASU 2023-09”), which enhances interim and annual income tax disclosures. The two primary enhancements disaggregate existing income tax disclosures related to the effective tax rate reconciliation and income taxes paid. The additional disclosure requirements under ASU 2023-09 are required to be applied prospectively and are effective for the Company on January 1, 2025. The Company does not expect the additional disclosure requirements under ASU 2023-09 to have a material impact on the consolidated financial statements.

Fair Value Measurements

Hierarchy of Fair Value Inputs. The Company uses a fair value hierarchy that prioritizes inputs to valuation approaches used to measure fair value. The fair value hierarchy gives the highest priority to quoted prices (unadjusted) in active markets for identical assets or liabilities and the lowest priority to unobservable inputs. Assets and liabilities measured and reported at fair value are classified and disclosed in one of the following categories:

Level 1 Inputs:

Quoted prices (unadjusted) in active markets for identical assets or liabilities at the reporting date.

•

Level 1 assets may include listed mutual funds, ETFs, listed equities, commodities and certain exchange-traded derivatives.

Level 2 Inputs:

Quoted prices for similar assets or liabilities in active markets; quoted prices for identical or similar assets or liabilities that are not active; quotes from pricing services or brokers for which the Company can determine that orderly transactions took place at the quoted price or that the inputs used to arrive at the price are observable; and inputs other than quoted prices that are observable, such as models or other valuation methodologies.

•

Level 2 assets may include debt securities, loans held within consolidated collateralized loan obligations (“CLOs”), short-term floating-rate notes, asset-backed securities, as well as over-the-counter derivatives, including interest rate swaps and foreign currency exchange contracts that have inputs to the valuations that generally can be corroborated by observable market data.

Level 3 Inputs:

Unobservable inputs for the valuation of the asset or liability, which may include nonbinding broker quotes. Level 3 assets include investments for which there is little, if any, market activity. These inputs require significant management judgment or estimation.

•

Level 3 assets may include direct private equity investments, including those held within CIPs, investments in CLOs, and loans held within consolidated CLOs and CIPs.

•

Level 3 liabilities may include borrowings of consolidated CLOs and contingent liabilities related to acquisitions valued based upon discounted cash flow analyses, using unobservable market data, or other valuation techniques.

Significance of Inputs. The Company’s assessment of the significance of a particular input to the fair value measurement in its entirety requires judgment and considers factors specific to the financial instrument.

Valuation Approaches. The fair values of certain Level 3 assets and liabilities were determined using various valuation approaches as appropriate, including third-party pricing vendors, broker quotes and market and income approaches.

A significant number of inputs used to value equity, debt securities, and loans held within CLOs and CIPs are sourced from third-party pricing vendors. Generally, prices obtained from pricing vendors are categorized as Level 1 inputs for identical securities traded in active markets and as Level 2 for other similar securities if the vendor uses observable inputs in determining the price.

In addition, quotes obtained from brokers generally are nonbinding and categorized as Level 3 inputs. However, if the Company is able to determine that market participants have transacted for the asset in an orderly manner near the quoted price or if the Company can determine that the inputs used by the broker are observable, the quote is classified as a Level 2 input.

Investments Measured at Net Asset Value. As a practical expedient, the Company uses net asset value (“NAV”) as the fair value for certain investments. The inputs to value these investments may include the Company’s capital accounts for its partnership interests in various alternative investments, including hedge funds, real assets and private equity funds, which may be adjusted by using the returns of certain market indices. The various partnerships are investment companies, which record their underlying investments at fair value based on fair value policies established by management of the underlying fund. Fair value policies at the underlying fund generally require the fund to utilize pricing/valuation information from third-party sources, including independent appraisals. However, in some instances, current valuation information for illiquid securities or securities in markets that are not active may not be available from any third-party source or fund management may conclude that the valuations that are available from third-party sources are not reliable. In these instances, fund management may perform model-based analytical valuations that could be used as an input to value these investments.

Fair Value Assets and Liabilities of Consolidated CLO. The Company applies the fair value option provisions for eligible assets, including loans, held by a consolidated CLO. As the fair value of the financial assets of the consolidated CLO is more observable than the fair value of the borrowings of the consolidated CLO, the Company measures the fair value of the borrowings of the consolidated CLO equal to the fair value of the assets of the consolidated CLO less the fair value of the Company’s economic interest in the CLO.

Derivatives and Hedging Activities

Derivatives and Hedging Activities. The Company does not use derivative financial instruments for trading or speculative purposes. The Company uses derivative financial instruments primarily for purposes of hedging exposures to fluctuations in foreign currency exchange rates of certain assets and liabilities, and market price and interest rate exposures with respect to its total portfolio of seed investments in sponsored investment products. Certain CIPs also utilize derivatives as a part of their investment strategies.

In addition, the Company uses derivatives and makes investments to economically hedge market valuation changes on certain deferred cash compensation plans, for which the final value of the deferred amount distributed to employees in cash upon vesting is determined based on the returns of specified investment funds. The Company recognizes compensation expense for the appreciation (depreciation) of the deferred cash compensation liability in proportion to the vested amount of the award during a respective period, while the gain (loss) to economically hedge these plans is immediately recognized in nonoperating income (expense). See Note 4, Investments, and Note 8, Derivatives and Hedging, for further information on the Company’s investments and derivatives, respectively, used to economically hedge these deferred cash compensation plans.

The Company records all derivative financial instruments as either assets or liabilities at fair value on a gross basis in the condensed consolidated statements of financial condition. Credit risks are managed through master netting and collateral support agreements. The amounts related to the right to reclaim or the obligation to return cash collateral may not be used to offset amounts due under the derivative instruments in the normal course of settlement. Therefore, such amounts are not offset against fair value amounts recognized for derivative instruments with the same counterparty and are included in other assets and other liabilities. Changes in the fair value of the Company’s derivative financial instruments are recognized in earnings and, where applicable, are offset by the corresponding gain or loss on the related foreign-denominated or hedged assets or liabilities, on the condensed consolidated statements of income.

The Company may also use financial instruments designated as net investment hedges for accounting purposes to hedge net investments in international subsidiaries, the functional currency of which is not United States ("US") dollars. The gain or loss from revaluing net investment hedges at the spot rate is deferred and reported within accumulated other comprehensive income (loss) (“AOCI”) on the condensed consolidated statements of financial condition. The Company reassesses the effectiveness of its net investment hedge at least quarterly.

Separate Account Assets and Liabilities

Separate Account Assets and Liabilities. Separate account assets are maintained by BlackRock Life Limited, a wholly owned subsidiary of the Company, which is a registered life insurance company in the United Kingdom (“UK”), and represent segregated assets held for purposes of funding individual and group pension contracts. The life insurance company does not underwrite any insurance contracts that involve any insurance risk transfer from the insured to the life insurance company. The separate account assets primarily include equity securities, debt securities, money market funds and derivatives. The separate account assets are not subject to general claims of the creditors of BlackRock. These separate account assets and the related equal and offsetting liabilities are recorded as separate account assets and separate account liabilities on the condensed consolidated statements of financial condition.

The net investment income attributable to separate account assets supporting individual and group pension contracts accrues directly to the contract owner and is not reported on the condensed consolidated statements of income. While BlackRock has no economic interest in these separate account assets and liabilities, BlackRock earns policy administration and management fees associated with these products, which are included in investment advisory, administration fees and securities lending revenue on the condensed consolidated statements of income.

Separate Account Collateral Assets Held and Liabilities Under Securities Lending Agreements

Separate Account Collateral Assets Held and Liabilities Under Securities Lending Agreements. The Company facilitates securities lending arrangements whereby securities held by separate accounts maintained by BlackRock Life Limited are lent to third parties under global master securities lending agreements. In exchange, the Company obtains either (1) the legal title, or (2) a first ranking priority security interest, in the collateral. The minimum collateral values generally range from approximately 102% to 112% of the value of the securities in order to reduce counterparty risk. The required collateral value is calculated on a daily basis. The global master securities lending agreements provide the Company the right to request additional collateral or, in the event of borrower default, the right to liquidate collateral. The securities lending transactions entered into by the Company are accompanied by an agreement that entitles the Company to request the borrower to return the securities at any time; therefore, these transactions are not reported as sales.

In situations where the Company obtains the legal title to collateral under these securities lending arrangements, the Company records an asset on the condensed consolidated statements of financial condition in addition to an equal collateral liability for the obligation to return the collateral. Additionally, in situations where the Company obtains a first ranking priority security interest in the collateral, the Company does not have the ability to pledge or resell the collateral and therefore does not record the collateral on the condensed consolidated statements of financial condition. At June 30, 2024 and December 31, 2023, the fair value of loaned securities held by separate accounts was approximately $9.5 billion and $9.3 billion, respectively, and the fair value of the collateral under these securities lending agreements was approximately $10.2 billion and $10.1 billion, respectively, of which approximately $5.0 billion as of June 30, 2024 and $4.6 billion as of December 31, 2023 was recognized on the condensed consolidated statements of financial condition. During the six months ended June 30, 2024 and 2023, the Company had not resold or repledged any of the collateral obtained under these arrangements. The securities lending revenue earned from lending securities held by the separate accounts is included in investment advisory, administration fees and securities lending revenue on the condensed consolidated statements of income.