BlackRock (BLK) 10-Q 8 Nov 13 2013 Q3 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	9 Months Ended
	Sep. 30, 2013	Oct. 31, 2013
Document And Entity Information [Abstract]	'	'
Document Type	'10-Q	'
Amendment Flag	'false	'
Document Period End Date	30-Sep-13	'
Document Fiscal Year Focus	'2013	'
Document Fiscal Period Focus	'Q3	'
Trading Symbol	'BLK	'
Entity Registrant Name	'BlackRock Inc.	'
Entity Central Index Key	'0001364742	'
Current Fiscal Year End Date	'--12-31	'
Entity Filer Category	'Large Accelerated Filer	'
Entity Common Stock, Shares Outstanding	'	167,090,120

Condensed_Consolidated_Stateme

Condensed Consolidated Statements of Financial Condition (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Assets	'	'
Cash and cash equivalents	$3,987	$4,606
Accounts receivable	4,311	2,250
Investments	1,878	1,750
Separate account assets	146,646	134,768
Separate account collateral held under securities lending agreements	21,962	23,021
Property and equipment (net of accumulated depreciation of $649 and $572 at September 30, 2013 and December 31, 2012, respectively)	523	557
Intangible assets (net of accumulated amortization of $1,019 and $899 at September 30, 2013 and December 31, 2012, respectively)	17,513	17,402
Goodwill	12,938	12,910
Other assets	759	626
Total assets	212,717	200,451
Liabilities	'	'
Accrued compensation and benefits	1,322	1,547
Accounts payable and accrued liabilities	3,322	1,055
Short-term borrowings	'	100
Long-term borrowings	4,938	5,687
Separate account liabilities	146,646	134,768
Separate account collateral liabilities under securities lending agreements	21,962	23,021
Deferred income tax liabilities	5,237	5,293
Other liabilities	948	858
Total liabilities	186,531	174,834
Commitments and contingencies (Note 12)	'	'
Temporary equity	'	'
Redeemable noncontrolling interests	41	32
Permanent Equity	'	'
Common stock, $0.01 par value; Shares authorized: 500,000,000 at September 30, 2013 and December 31, 2012; Shares issued: 171,252,185 at September 30, 2013 and December 31, 2012; Shares outstanding: 167,277,854 and 168,875,304 at September 30, 2013 and December 31, 2012, respectively	2	2
Preferred stock (Note 16)	'	'
Additional paid-in capital	19,391	19,419
Retained earnings	7,653	6,444
Accumulated other comprehensive loss	-79	-59
Treasury stock, common, at cost (3,974,331 and 2,376,881 shares held at September 30, 2013 and December 31, 2012, respectively)	-993	-432
Total BlackRock, Inc. stockholders' equity	25,999	25,403
Nonredeemable noncontrolling interests	127	155
Total permanent equity	26,145	25,585
Total liabilities, temporary equity and permanent equity	212,717	200,451
Variable Interest Entity, Primary Beneficiary, Aggregated Disclosure [Member]	'	'
Assets	'	'
Cash and cash equivalents	93	297
Bank loans, other investments and other assets	2,107	2,264
Liabilities	'	'
Borrowings	2,068	2,402
Other liabilities	88	103
Permanent Equity	'	'
Appropriated retained earnings	25	29
Nonredeemable noncontrolling interests	$19	$27

Condensed_Consolidated_Stateme1

Condensed Consolidated Statements of Financial Condition (Parenthetical) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Millions, except Share data, unless otherwise specified
Statement Of Financial Position [Abstract]	'	'
Property and equipment, accumulated depreciation	$649	$572
Intangible assets, accumulated amortization	$1,019	$899
Common stock, par value	$0.01	$0.01
Common stock, shares authorized	500,000,000	500,000,000
Common stock, shares issued	171,252,185	171,252,185
Common stock, shares outstanding	167,277,854	168,875,304
Treasury stock, common shares	3,974,331	2,376,881

Condensed_Consolidated_Stateme2

Condensed Consolidated Statements of Income (USD $)	3 Months Ended		9 Months Ended
In Millions, except Share data, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Revenue	'	'	'	'
Total investment advisory, administration fees and securities lending revenue	$2,153	$2,024	$6,459	$5,991
Investment advisory performance fees	96	103	293	224
BlackRock Solutions and advisory	156	128	420	382
Distribution fees	19	19	54	58
Other revenue	48	46	177	143
Total revenue	2,472	2,320	7,403	6,798
Expenses	'	'	'	'
Employee compensation and benefits	866	828	2,635	2,439
Distribution and servicing costs	85	94	266	282
Amortization of deferred sales commissions	14	13	38	43
Direct fund expenses	167	144	490	440
General and administration	334	327	1,130	958
Amortization of intangible assets	40	39	120	117
Total expenses	1,506	1,445	4,679	4,279
Operating income	966	875	2,724	2,519
Nonoperating income (expense)	'	'	'	'
Net gain (loss) on investments	32	75	235	143
Interest and dividend income	8	10	18	27
Interest expense	-52	-57	-159	-158
Total nonoperating income (expense)	-18	30	92	13
Income before income taxes	948	905	2,816	2,532
Income tax expense	219	250	715	742
Net income	729	655	2,101	1,790
Less:	'	'	'	'
Net income (loss) attributable to redeemable noncontrolling interests	'	3	-1	7
Net income (loss) attributable to nonredeemable noncontrolling interests	-1	10	11	15
Net income attributable to BlackRock, Inc.	730	642	2,091	1,768
Earnings per share attributable to BlackRock, Inc. common stockholders:	'	'	'	'
Basic	$4.30	$3.72	$12.26	$10.02
Diluted	$4.21	$3.65	$12.02	$9.87
Cash dividends declared and paid per share	$1.68	$1.50	$5.04	$4.50
Weighted-average common shares outstanding:	'	'	'	'
Basic	169,811,633	172,359,141	170,581,930	176,116,975
Diluted	173,371,508	175,450,532	174,012,876	178,956,699
Variable Interest Entity, Primary Beneficiary, Aggregated Disclosure [Member]	'	'	'	'
Nonoperating income (expense)	'	'	'	'
Net gain (loss) on consolidated variable interest entities	-6	2	-2	1
Related parties [Member]	'	'	'	'
Revenue	'	'	'	'
Total investment advisory, administration fees and securities lending revenue	1,478	1,319	4,403	3,900
Other third parties [Member]	'	'	'	'
Revenue	'	'	'	'
Total investment advisory, administration fees and securities lending revenue	$675	$705	$2,056	$2,091

Condensed_Consolidated_Stateme3

Condensed Consolidated Statements of Comprehensive Income (USD $)	3 Months Ended				9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013		Sep. 30, 2012		Sep. 30, 2013		Sep. 30, 2012
Statement Of Income And Comprehensive Income [Abstract]	'		'		'		'
Net income	$729		$655		$2,101		$1,790
Other comprehensive income (loss):	'		'		'		'
Unrealized holding gains (losses), net of tax	2		10		3		12
Less: reclassification adjustment included in net income	1	[1]	-4	[1]	10	[1]	-5	[1]
Net change from available-for-sale investments, net of tax	1		14		-7		17
Benefit plans, net of tax	'		'		'		-1	[2]
Foreign currency translation adjustments	118		54		-13		53
Other comprehensive income (loss)	119		68		-20		69
Comprehensive income	848		723		2,081		1,859
Less: Comprehensive income (loss) attributable to noncontrolling interests	-1		13		10		22
Comprehensive income attributable to BlackRock, Inc.	$849		$710		$2,071		$1,837
[1]	The tax benefit (expense) was not material for the three and nine months ended September 30, 2013 and 2012.
[2]	The tax benefit (expense) for the nine months ended September 30, 2012 was not material.

Condensed_Consolidated_Stateme4

Condensed Consolidated Statements of Comprehensive Income (Parenthetical) (USD $)	3 Months Ended		9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Statement Of Income And Comprehensive Income [Abstract]	'	'	'	'
Tax benefit (expense) on unrealized holding gains (losses)	$0	($7)	$0	($8)

Condensed_Consolidated_Stateme5

Condensed Consolidated Statements of Changes in Equity (USD $)

Total

Additional Paid-in Capital [Member]

Retained Earnings [Member]

Appropriated Retained Earnings [Member]

Accumulated Other Comprehensive Income (Loss) [Member]

Treasury Stock Common [Member]

Total Stockholders' Equity [Member]

Nonredeemable Noncontrolling Interests [Member]

Nonredeemable Noncontrolling Interests of Consolidated VIEs [Member]

Total Permanent Equity [Member]

Redeemable Noncontrolling Interests/Temporary Equity [Member]

Common Shares Held in Escrow [Member]

In Millions

Beginning Balance at Dec. 31, 2011

'

$20,276

[1]

$5,046

$72

($127)

($218)

$25,048

$184

$38

$25,270

$92

[2]

($1)

Net income

'

'

1,768

'

'

'

1,768

14

1

1,783

7

[2]

'

Allocation of gains (losses) of consolidated collateralized loan obligations

'

'

'

-3

'

'

-3

'

3

'

'

'

Dividends paid

'

'

-804

'

'

'

-804

'

'

-804

'

'

Stock-based compensation

'

344

[1]

'

'

'

'

344

'

'

344

'

'

Issuance of common shares related to employee stock transactions

'

-366

[1]

'

'

'

419

53

'

'

53

'

'

Employee tax benefit withholdings related to employee stock transactions

'

'

'

'

'

-141

-141

'

'

-141

'

'

Net tax benefit (shortfall) from stock-based compensation

'

63

[1]

'

'

'

'

63

'

'

63

'

'

Subscriptions (redemptions/distributions) - noncontrolling interest holders

'

'

'

'

'

'

'

-20

-8

-28

221

[2]

'

Net consolidations (deconsolidations) of sponsored investment funds

'

'

'

'

'

'

'

-8

'

-8

-272

[2]

'

Other comprehensive income (loss)

69

'

'

'

69

'

69

'

'

69

'

'

Consolidation of a collateralized loan obligation

[3]

'

'

'

-13

'

'

-13

'

'

-13

'

'

Merrill Lynch cash capital contribution

'

7

[1]

'

'

'

'

7

'

'

7

'

'

Shares repurchased

'

-1,000

[1]

'

'

'

-334

-1,334

'

'

-1,334

'

'

Ending Balance at Sep. 30, 2012

'

19,324

[1]

6,010

56

-58

-274

25,057

170

34

25,261

48

[2]

-1

Beginning Balance at Dec. 31, 2012

25,585

19,421

[1]

6,444

29

-59

-432

25,403

155

27

25,585

32

'

Net income

'

'

2,091

'

'

'

2,091

13

-2

2,102

-1

'

Allocation of gains (losses) of consolidated collateralized loan obligations

'

'

'

-4

'

'

-4

'

4

'

'

'

Dividends paid

'

'

-882

'

'

'

-882

'

'

-882

'

'

Stock-based compensation

'

339

[1]

'

'

'

1

340

'

'

340

'

'

Issuance of common shares related to employee stock transactions

'

-402

[1]

'

'

'

422

20

'

'

20

'

'

Employee tax benefit withholdings related to employee stock transactions

'

'

'

'

'

-234

-234

'

'

-234

'

'

Shares repurchased

'

'

'

'

'

-750

-750

'

'

-750

'

'

Net tax benefit (shortfall) from stock-based compensation

'

35

[1]

'

'

'

'

35

'

'

35

'

'

Subscriptions (redemptions/distributions) - noncontrolling interest holders

'

'

'

'

'

'

'

-41

124

83

104

'

Net consolidations (deconsolidations) of sponsored investment funds

'

'

'

'

'

'

'

'

-134

-134

-94

'

Other comprehensive income (loss)

-20

'

'

'

-20

'

-20

'

'

-20

'

'

Ending Balance at Sep. 30, 2013

$26,145

$19,393

[1]

$7,653

$25

($79)

($993)

$25,999

$127

$19

$26,145

$41

'

[1]

Amounts include $2 million of common stock at both September 30, 2013 and December 31, 2012.

[2]

Amounts include $2 million and $1 million of common stock at September 30, 2012 and December 31, 2011, respectively.

[3]

Amount at September 30, 2012 includes $20 million related to variable interest entities.

Condensed_Consolidated_Stateme6

Condensed Consolidated Statements of Changes in Equity (Parenthetical) (USD $)	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2012	Dec. 31, 2011
In Millions, unless otherwise specified
Temporary equity	$41	$32	'	'
Common Stock [Member]	'	'	'	'
Additional Paid-in Capital, value of stock	2	2	2	1
Variable Interest Entity, Primary Beneficiary, Aggregated Disclosure [Member]	'	'	'	'
Temporary equity	'	'	$20	'

Condensed_Consolidated_Stateme7

Condensed Consolidated Statements of Cash Flows (USD $)	9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012
Cash flows from operating activities	'	'
Net income	$2,101	$1,790
Adjustments to reconcile net income to cash flows from operating activities:	'	'
Depreciation and amortization	215	219
Amortization of deferred sales commissions	38	43
Stock-based compensation	340	344
Deferred income tax expense (benefit)	-44	-42
Gain related to PennyMac initial public offering	-39	'
Gain related to the charitable contribution	-80	'
Charitable contribution	124	'
Net (gains) losses on nontrading investments	-46	-32
Purchases of investments within consolidated sponsored investment funds	-45	-83
Proceeds from sales and maturities of investments within consolidated sponsored investment funds	112	48
Assets and liabilities of consolidated VIEs:	'	'
Change in cash and cash equivalents	204	-32
Net (gains) losses within consolidated VIEs	2	-1
Net (purchases) proceeds within consolidated VIEs	15	233
(Earnings) losses from equity method investees	-110	-124
Distributions of earnings from equity method investees	39	29
Changes in operating assets and liabilities:	'	'
Accounts receivable	-2,061	-493
Deferred sales commissions	-42	-31
Investments, trading	-205	-197
Other assets	-97	-173
Accrued compensation and benefits	-225	-199
Accounts payable and accrued liabilities	2,264	489
Other liabilities	16	98
Cash flows from operating activities	2,476	1,886
Cash flows from investing activities	'	'
Purchases of investments	-188	-397
Proceeds from sales and maturities of investments	225	391
Distributions of capital from equity method investees	51	51
Net consolidations (deconsolidations) of sponsored investment funds	-63	-208
Acquisitions, net of cash acquired	-240	-267
Purchases of property and equipment	-60	-121
Cash flows from investing activities	-275	-551
Cash flows from financing activities	'	'
Repayments of short-term borrowings	-100	'
Repayments of long-term borrowings	-750	'
Proceeds from long-term borrowings	'	1,495
Cash dividends paid	-882	-804
Proceeds from stock options exercised	15	47
Proceeds from issuance of common stock	5	6
Repurchases of common stock	-984	-1,475
Merrill Lynch cash capital contribution	'	7
Net proceeds from (repayments of) borrowings by consolidated VIEs	-343	-203
Net (redemptions/distributions paid) subscriptions received from noncontrolling interests holders	187	193
Excess tax benefit from stock-based compensation	40	73
Cash flows from financing activities	-2,812	-661
Effect of exchange rate changes on cash and cash equivalents	-8	43
Net increase (decrease) in cash and cash equivalents	-619	717
Cash and cash equivalents, beginning of period	4,606	3,506
Cash and cash equivalents, end of period	3,987	4,223
Supplemental disclosure of cash flow information:	'	'
Interest	125	116
Interest on borrowings of consolidated VIEs	82	52
Income taxes	746	837
Supplemental schedule of noncash investing and financing transactions:	'	'
Issuance of common stock	402	366
Increase (decrease) in noncontrolling interests due to net consolidation (deconsolidation) of sponsored investment funds	-228	-280
Increase (decrease) in borrowings due to consolidation of VIEs	'	$406

Business_Overview

Business Overview	9 Months Ended
	Sep. 30, 2013
Accounting Policies [Abstract]	'
Business Overview	'
	1. Business Overview
	BlackRock, Inc. (together, with its subsidiaries, unless the context otherwise indicates, “BlackRock” or the “Company”) provides diversified investment management services to institutional clients, intermediary and individual investors through various investment vehicles. Investment management services primarily consist of the management of equity, fixed income, multi-asset, alternative investment and cash management products. BlackRock offers investment products in a variety of vehicles, including open-end and closed-end mutual funds, iShares® exchange-traded funds (“ETFs”), collective investment trusts and separate accounts. In addition, BlackRock provides market risk management, financial markets advisory and enterprise investment system services to a broad base of clients. Financial markets advisory services include valuation services relating to illiquid securities, dispositions and workout assignments (including long-term portfolio liquidation assignments), risk management and strategic planning and execution.
	At September 30, 2013, The PNC Financial Services Group, Inc. (“PNC”) held 20.9% of the Company’s voting common stock and 21.9% of the Company’s capital stock, which includes outstanding common and nonvoting preferred stock.

Significant_Accounting_Policie

Significant Accounting Policies	9 Months Ended
	Sep. 30, 2013
Accounting Policies [Abstract]	'
Significant Accounting Policies	'
	2.  Significant Accounting Policies
	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 on the condensed consolidated statements of financial condition include the portion of consolidated sponsored investment funds in which the Company does not have direct equity ownership. Significant accounts and transactions between consolidated entities have been eliminated.
	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 revenues and expenses 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 notes related thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2012, which was filed with the Securities and Exchange Commission (“SEC”) on March 1, 2013 (“2012 Form 10-K”).
	The interim financial information at September 30, 2013 and for the three and nine months ended September 30, 2013 and 2012 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 indicative of results to be expected for the full year.
	Fair Value Measurements.
	Hierarchy of Fair Value Inputs.    The provisions of Accounting Standards Codification (“ASC”) 820-10, Fair Value Measurements and Disclosures (“ASC 820-10”), establish a hierarchy that prioritizes inputs to valuation techniques used to measure fair value and require companies to disclose the fair value of their financial instruments according to the fair value hierarchy (i.e., Level 1, 2 and 3 inputs, as defined). 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 (including those accounted for under the equity method of accounting as these mutual funds are investment companies that have publicly available net asset values (“NAVs”), which in accordance with GAAP, are calculated under fair value measures and the changes in fair values are equal to the earnings of such funds), ETFs, listed equities 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. As a practical expedient, the Company relies on the NAV (or its equivalent) of certain investments as their fair value.
		•	Level 2 assets may include debt securities, bank loans, short-term floating-rate notes and asset-backed securities, securities held within consolidated hedge funds, certain equity method limited partnership interests in hedge funds valued based on NAV (or its equivalent) where the Company has the ability to redeem at the measurement date or within the near term without redemption restrictions, restricted public securities valued at a discount, as well as over-the-counter derivatives, including interest and inflation 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. Certain investments that are valued using a NAV (or its equivalent) and are subject to current redemption restrictions that will not be lifted in the near term are included in Level 3.
		•	Level 3 assets may include general and limited partnership interests in private equity funds, funds of private equity funds, real estate funds, hedge funds and funds of hedge funds, direct private equity investments held within consolidated funds, bank loans and bonds.
		•	Level 3 liabilities include borrowings of consolidated collateralized loan obligations (“CLOs”) valued based upon nonbinding single-broker quotes.
		•	Level 3 inputs include BlackRock capital accounts for its partnership interests in various alternative investments, including distressed credit hedge funds, real estate and private equity funds, which may be adjusted by using the returns of certain market indices.
	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 Techniques.    The fair values of certain Level 3 assets and liabilities were determined using various methodologies as appropriate, including NAVs of underlying investments, third-party pricing vendors, broker quotes and market and income approaches. Such quotes and modeled prices are evaluated for reasonableness through various procedures, including due diligence reviews of third-party pricing vendors, variance analyses, consideration of the current market environment and other analytical procedures.
	As a practical expedient, the Company relies on NAV as the fair value for certain investments. The inputs to value these investments may include BlackRock capital accounts for its partnership interests in various alternative investments, including distressed credit hedge funds, real estate 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 may be used as an input to value these investments.
	A significant amount of inputs used to value equity, debt securities and bank loans is sourced from well-recognized 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. Annually, BlackRock’s internal valuation committee or other designated groups review both the valuation methodologies, including the general assumptions and methods used to value various asset classes, and operational processes with these vendors. In addition, on a quarterly basis, meetings are held with the vendors to identify any significant changes to the vendors’ processes.
	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.
	Fair Value Option.    ASC 825-10, Financial Instruments (“ASC 825-10”), provides a fair value option election that allows companies an irrevocable election to use fair value as the initial and subsequent accounting measurement attribute for certain financial assets and liabilities. ASC 825-10 permits entities to elect to measure eligible financial assets and liabilities at fair value on an ongoing basis. Unrealized gains and losses on items for which the fair value option has been elected are reported in earnings. The decision to elect the fair value option is determined on an instrument-by-instrument basis, which must be applied to an entire instrument, and not only specified risks, specific cash flows, or portions of that instrument, and is irrevocable once elected. Assets and liabilities measured at fair value pursuant to ASC 825-10 are required to be reported separately from those instruments measured using another accounting method.
	Derivative Instruments and Hedging Activities.    ASC 815-10, Derivatives and Hedging (“ASC 815-10”), establishes accounting and reporting standards for derivative instruments, including certain derivatives embedded in other contracts and for hedging activities. ASC 815-10 generally requires an entity to recognize all derivatives as either assets or liabilities on the condensed consolidated statements of financial condition and to measure those investments at fair value.
	The Company does not use derivative financial instruments for trading or speculative purposes. The Company uses derivative financial instruments primarily for purposes of hedging: (i) exposures to fluctuations in foreign currency exchange rates of certain assets and liabilities, (ii) market exposures for certain seed investments and (iii) future cash flows on floating-rate notes. The Company may also use derivatives within its separate account assets, which are segregated funds held for purposes of funding individual and group pension contracts. In addition, certain consolidated sponsored investment funds may also invest in derivatives as a part of their investment strategy.
	Changes in the fair value of the Company’s derivative financial instruments are generally recognized in earnings and, where applicable, are offset by the corresponding gain or loss on the related foreign-denominated assets or liabilities or hedged investments, on the condensed consolidated statements of income.
	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, 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, 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 in accordance with the ASC 944-80, Financial Services – Separate Accounts.
	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.    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 receives collateral with minimum values generally ranging from approximately 102% to 112% of the value of the securities lent 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, in the event of customer default, the right to liquidate collateral or to request additional collateral. Under the Company’s securities lending arrangements, the Company can resell or re-pledge the collateral and the borrower can resell or re-pledge the loaned securities. 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 under ASC 860, Transfers and Servicing.
	As a result of the Company’s ability to resell or re-pledge the collateral, the Company records on the condensed consolidated statements of financial condition the cash and noncash collateral received under these arrangements as its own asset in addition to an equal and offsetting collateral liability for the obligation to return the collateral. During the nine months ended September 30, 2013 and 2012, the Company had not re-sold or re-pledged any of the collateral received under these arrangements. At September 30, 2013 and December 31, 2012, the fair value of loaned securities held by separate account assets was approximately $20.2 billion and $21.0 billion, respectively, and the fair value of the collateral held under these securities lending agreements was approximately $22.0 billion and $23.0 billion, respectively.
	Appropriated Retained Earnings.    Upon the initial consolidation of CLOs, BlackRock records a cumulative effect adjustment to appropriated retained earnings on the condensed consolidated statements of financial condition equal to the difference between the fair value of the CLOs’ assets and the fair value of their liabilities. Such amounts are recorded as appropriated retained earnings as the CLO noteholders, not BlackRock, ultimately will receive the benefits or absorb the losses associated with the CLOs’ assets and liabilities. The net change in the fair value of the CLOs’ assets and liabilities is recorded as net income (loss) attributable to nonredeemable noncontrolling interests and as an adjustment to appropriated retained earnings.
	Accounting Pronouncements Adopted in the Nine Months Ended September 30, 2013
	Amendments to Accumulated Other Comprehensive Income Disclosures.    On February 5, 2013, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2013-02, Reporting of Amounts Reclassified Out of Accumulated Other Comprehensive Income (“ASU 2013-02”), which added new disclosure requirements for items reclassified out of accumulated other comprehensive income (“AOCI”). See Note 15, Accumulated Other Comprehensive Income (Loss).
	Disclosures About Offsetting Assets and Liabilities.    On December 16, 2011, the FASB issued ASU 2011-11, Disclosures About Offsetting Assets and Liabilities (“ASU 2011-11”), which created new disclosure requirements about the nature of an entity’s rights of setoff and related arrangements associated with its financial instruments and derivative instruments. On January 31, 2013, the FASB issued ASU 2013-01, Clarifying the Scope of Disclosures about Offsetting Assets and Liabilities (“ASU 2013-01”), that provides clarification about which instruments and transactions are subject to ASU 2011-11. The adoption of ASU 2011-11 and ASU 2013-01 on January 1, 2013 was not material to the condensed consolidated financial statements.
	Benchmark Interest Rate for Hedge Accounting.    In July 2013, the FASB issued ASU 2013-10, Inclusion of the Fed Funds Effective Swap Rate (or Overnight Index Swap Rate) as a Benchmark Interest Rate for Hedge Accounting Purposes (“ASU 2013-10”). ASU 2013-10 provides for the inclusion of certain interest rate benchmarks for hedge accounting purposes. The adoption of ASU 2013-10 in the third quarter 2013 did not have a material impact on the condensed consolidated financial statements.
	Recent Accounting Pronouncements Not Yet Adopted
	Cumulative Translation Adjustment.    In March 2013, the FASB issued ASU 2013-05, Parent’s Accounting for the Cumulative Translation Adjustment upon Derecognition of Certain Subsidiaries or Groups of Assets within a Foreign Entity or of an Investment in a Foreign Entity (“ASU 2013-05”).    ASU 2013-05 addresses the accounting for the cumulative translation adjustment when a parent either sells a part or all of its investment in a foreign entity or no longer holds a controlling financial interest in a subsidiary or group of assets that is a nonprofit activity or a business within a foreign entity. ASU 2013-05 is effective for the Company on January 1, 2014. The Company does not believe the adoption of ASU 2013-05 will have a material impact on the condensed consolidated financial statements.
	Investment Company Guidance.    In June 2013, the FASB issued ASU 2013-08, Financial Services — Investment Companies: Amendments to the Scope, Measurement, and Disclosure Requirements (“ASU 2013-08”). ASU 2013-08 amends the current criteria for an entity to qualify as an investment company, creates new disclosure requirements and amends the measurement criteria for certain interests in other investment companies. ASU 2013-08 is effective for the Company on January 1, 2014. The Company does not believe the adoption of ASU 2013-08 will have a material impact on the condensed consolidated financial statements.
	Presentation of an Unrecognized Tax Benefit.    In July 2013, the FASB issued ASU 2013-11, Presentation of an Unrecognized Tax Benefit When a Net Operating Loss Carryforward, a Similar Tax Loss, or a Tax Credit Carryforward Exists (“ASU 2013-11”). ASU 2013-11 provides guidance on the financial statement presentation of an unrecognized tax benefit when a net operating loss carryforward, a similar tax loss, or a tax credit carryforward exists. ASU 2013-11 is effective for the Company on January 1, 2014. The Company does not believe the adoption of ASU 2013-11 will have a material impact on the condensed consolidated financial statements.

Investments

Investments	9 Months Ended
	Sep. 30, 2013
Investments Debt And Equity Securities [Abstract]	'
Investments	'
	3.  Investments
	A summary of the carrying value of investments is as follows:
	(in millions)		September 30,				December 31,
			2013				2012
	Available-for-sale investments			$168				$158
	Held-to-maturity investments			57				112
	Trading investments:
	Consolidated sponsored investment funds			381				123
	Other equity and debt securities			67				94
	Deferred compensation plan mutual funds			57				53
	Total trading investments			505				270
	Other investments:
	Consolidated sponsored investment funds			314				401
	Equity method investments			564				595
	Deferred compensation plan hedge fund equity method investments			11				9
	Cost method investments(1)			122				120
	Carried interest			137				85
	Total other investments			1,148				1,210
	Total investments			$1,878				$1,750
		(1)	Amounts primarily include Federal Reserve Bank Stock.
	At September 30, 2013, the Company consolidated $695 million of investments held by consolidated sponsored investment funds (excluding variable interest entities (“VIEs”)) of which $381 million and $314 million were classified as trading investments and other investments, respectively. At December 31, 2012, the Company consolidated $524 million of investments held by consolidated sponsored investment funds (excluding VIEs) of which $123 million and $401 million were classified as trading investments and other investments, respectively.
	Available-for-Sale Investments
	A summary of the cost and carrying value of investments classified as available-for-sale investments is as follows:
	(in millions)
							Gross Unrealized						Carrying
	At September 30, 2013		Cost				Gains				Losses		Value
	Equity securities of sponsored investment funds			$163				$6				($4)		$165
	Other securities			1				2				-		3
	Total available-for-sale investments			$164				$8				($4)		$168
	At December 31, 2012
	Equity securities of sponsored investment funds			$142				$14				($1)		$155
	Other securities			2				1				-		3
	Total available-for-sale investments			$144				$15				($1)		$158
	Available-for-sale investments primarily included seed investments in BlackRock sponsored investment mutual funds.
	Held-to-Maturity Investments
	The carrying value of held-to-maturity investments was $57 million and $112 million at September 30, 2013 and December 31, 2012, respectively. Held-to-maturity investments included foreign government debt held for regulatory purposes and the amortized cost (carrying value) of these investments approximated fair value. At September 30, 2013, $43 million of these investments would mature in one year or less and $14 million would mature after 10 years.
	Trading Investments
	A summary of the cost and carrying value of trading investments is as follows:
	(in millions)		September 30, 2013						December 31, 2012
			Cost		Carrying				Cost		Carrying
					Value						Value
	Trading investments:
	Deferred compensation plan mutual funds			$  51		$  57				$  46		$  53
	Equity/Multi-asset mutual funds			190		194				154		162
	Debt securities/fixed income mutual funds:
	Corporate debt			126		126				44		44
	Government debt			132		128				11		11
	Total trading investments			$499		$505				$255		$270
	At September 30, 2013, trading investments included $187 million of equity securities and $194 million of debt securities held by consolidated sponsored investment funds, $57 million of deferred compensation plan mutual fund investments and $67 million of other equity and debt securities.
	Other Investments
	A summary of the cost and carrying value of other investments is as follows:
	(in millions)		September 30, 2013						December 31, 2012
			Cost		Carrying				Cost		Carrying
					Value						Value
	Other investments:
	Consolidated sponsored investment funds			$303		$314				$378		$401
	Equity method			480		564				541		595
	Deferred compensation plan hedge fund			9		11				15		9
	equity method investments
	Cost method investments:
	Federal Reserve Bank stock			93		93				89		89
	Other			17		29				31		31
	Total cost method investments			110		122				120		120
Carried interest			-		137				-		85
Total other investments			$902		$1,148				$1,054		$1,210
Consolidated sponsored investment funds include third-party private equity funds, direct investments in private companies and third-party hedge funds held by BlackRock sponsored investment funds.
Equity method investments primarily include BlackRock’s direct investment in certain BlackRock sponsored investment funds. See Note 10, Other Assets, for information on the Company’s investment in PennyMac Financial Services, Inc. (“PennyMac”), which is included in other assets on the condensed consolidated statements of financial condition.
Cost method investments include nonmarketable securities, including Federal Reserve Bank stock, which is held for regulatory purposes and is restricted from sale. At September 30, 2013 and December 31, 2012, there were no indicators of impairment on these investments.
Carried interest represents allocations to BlackRock’s general partner capital accounts from certain funds. These balances are subject to change upon cash distributions, additional allocations or reallocations back to limited partners within the respective funds.

Consolidated_Sponsored_Investm

Consolidated Sponsored Investment Funds	9 Months Ended
	Sep. 30, 2013
Text Block [Abstract]	'
Consolidated Sponsored Investment Funds	'
	4.  Consolidated Sponsored Investment Funds
	The Company consolidates certain sponsored investment funds primarily because it is deemed to control such funds. The investments owned by these consolidated sponsored investment funds are classified as trading or other investments. The following table presents the balances related to these consolidated funds that were included on the condensed consolidated statements of financial condition as well as BlackRock’s net interest in these funds:
	(in millions)	September 30,		December 31,
		2013		2012
	Cash and cash equivalents		$105		$133
	Investments:
	Trading investments		381		123
	Other investments		314		401
	Other assets		13		25
	Other liabilities		-33		-65
	Noncontrolling interests		-168		-187
	BlackRock’s net interests in consolidated sponsored investment funds		$612		$430
	BlackRock’s total exposure to consolidated sponsored investment funds of $612 million and $430 million at September 30, 2013 and December 31, 2012, respectively, represents the value of the Company’s economic ownership interest in these sponsored investment funds. Valuation changes associated with these consolidated investment funds are reflected in nonoperating income (expense) and partially offset in net income (loss) attributable to noncontrolling interests for the portion not attributable to BlackRock.
	In addition, at September 30, 2013 and December 31, 2012, several consolidated CLOs and one investment fund, which were deemed to be VIEs, were excluded from the balances in the table above as the balances for these investment products are reported separately on the condensed consolidated statements of financial condition. See Note 6, Variable Interest Entities, for further discussion of these consolidated investment products.
	The Company is not able to access cash and cash equivalents held by consolidated sponsored investment funds to use in its operating activities. In addition, the Company is not able to sell investments held by consolidated sponsored investment funds in order to obtain cash for use in the Company’s operations.

Fair_Value_Disclosures

Fair Value Disclosures	9 Months Ended
	Sep. 30, 2013
Fair Value Disclosures [Abstract]	'
Fair Value Disclosures	'
	5.  Fair Value Disclosures
	Assets and liabilities measured at fair value on a recurring basis and other assets not held at fair value
	September 30, 2013		Quoted			Significant Other			Significant		Other Assets			September 30,
	(in millions)		Prices in			Observable Inputs			Unobservable		Not Held at Fair			2013
			Active			(Level 2)			Inputs		Value(1)
			Markets for						(Level 3)
			Identical
			Assets
			(Level 1)
	Assets:
	Investments
	Available-for-sale:
	Equity securities (funds and CDOs)		$	165		$	-		$	1	$	-		$	166
	Debt securities			-			2			-		-			2
	Total available-for-sale			165			2			1		-			168
	Held-to-maturity debt securities			-			-			-		57			57
	Trading:
	Deferred compensation plan mutual funds			57			-			-		-			57
	Equity/Multi-asset mutual funds			194			-			-		-			194
	Debt securities / fixed income mutual funds			61			193			-		-			254
	Total trading			312			193			-		-			505
	Other investments:
	Consolidated sponsored investment funds:
	Hedge funds / Funds of funds			1			21			45		-			67
	Private / public equity(2)			5			8			234		-			247
	Total consolidated sponsored investment funds			6			29			279		-			314
	Equity method:
	Hedge funds / Funds of hedge funds			-			67			145		55			267
	Private equity investments			-			-			98		-			98
	Real estate funds			-			20			103		7			130
	Fixed income mutual funds			63			-			-		-			63
	Equity/Multi-asset, alternative mutual funds			6			-			-		-			6
	Total equity method			69			87			346		62			564
	Deferred compensation plan hedge fund equity method investments			-			11			-		-			11
	Cost method investments			-			-			-		122			122
	Carried interest			-			-			-		137			137
	Total investments			552			322			626		378			1,878
	Separate account assets			106,085			39,675			-		886			146,646
	Separate account collateral held under securities lending agreements:
	Equity securities			19,851			-			-		-			19,851
	Debt securities			-			2,111			-		-			2,111
	Total separate account collateral held under securities lending agreements			19,851			2,111			-		-			21,962
	Other assets(3)			-			12			-		-			12
	Assets of consolidated VIEs:
	Bank loans and other assets			-			1,867			97		20			1,984
	Bonds			-			64			35		-			99
	Private / public equity(4)			-			7			17		-			24
	Total assets of consolidated VIEs			-			1,938			149		20			2,107
	Total		$	126,488		$	44,058		$	775	$	1,284		$	172,605
	Liabilities:
	Borrowings of consolidated VIEs		$	-		$	-		$	2,068	$	-		$	2,068
	Separate account collateral liabilities under securities lending agreements			19,851			2,111			-		-			21,962
	Other liabilities(5)			19			4			33		-			56
	Total		$	19,870		$	2,115		$	2,101	$	-		$	24,086
		(1)	Amounts are comprised of investments held at cost or amortized cost, carried interest and certain equity method investments, which include investment companies and other assets, which in accordance with GAAP are not accounted for under a fair value measure. In accordance with GAAP, certain equity method investees do not account for both their financial assets and liabilities under fair value measures; therefore, the Company’s investment in such equity method investees may not represent fair value.
		(2)	Level 3 amounts include $202 million and $32 million of underlying third-party private equity funds and direct investments in private equity companies held by private equity funds, respectively.
		(3)	Amount includes company-owned and split-dollar life insurance policies.
		(4)	Level 3 amounts include $15 million and $2 million of underlying third-party private equity funds and direct investments in private equity companies held by a private equity fund.
		(5)	Amounts include a credit default swap (see Note 7, Derivatives and Hedging, for more information), securities sold short within consolidated sponsored investment funds and a contingent liability related to the acquisition of Credit Suisse’s ETF franchise.
	Assets and liabilities measured at fair value on a recurring basis and other assets not held at fair value
	December 31, 2012		Quoted			Significant			Significant		Other Assets			December 31,
	(in millions)		Prices in			Other			Unobservable		Not Held at			2012
			Active			Observable			Inputs		Fair Value (1)
	Markets for		Inputs			(Level 3)
	Identical		(Level 2)
	Assets
	(Level 1)
Assets:
Investments
Available-for-sale:
Equity securities (funds and CDOs)		$	155		$	-		$	1	$	-		$	156
Debt securities			-			2			-		-			2
Total available-for-sale			155			2			1		-			158
Held-to-maturity debt securities			-			-			-		112			112
Trading:
Deferred compensation plan mutual funds			53			-			-		-			53
Equity/Multi-asset mutual funds			159			3			-		-			162
Debt securities / fixed income mutual funds			5			50			-		-			55
Total trading			217			53			-		-			270
Other investments:
Consolidated sponsored investment funds:
Hedge funds / Funds of funds			3			39			73		-			115
Private / public equity(2)			10			10			266		-			286
Total consolidated sponsored investment funds			13			49			339		-			401
Equity method:
Hedge funds / Funds of hedge funds			-			61			161		39			261
Private equity investments			-			-			90		-			90
Real estate funds			-			19			88		15			122
Fixed income mutual funds			46			-			-		-			46
Equity/Multi-asset, alternative mutual funds			76			-			-		-			76
Total equity method			122			80			339		54			595
Deferred compensation plan hedge fund equity method investments			-			9			-		-			9
Cost method investments			-			-			-		120			120
Carried interest			-			-			-		85			85
Total investments			507			193			679		371			1,750
Separate account assets			95,514			38,392			2		860			134,768
Separate account collateral held under securities lending agreements:
Equity securities			21,273			-			-		-			21,273
Debt securities			-			1,748			-		-			1,748
Total separate account collateral held under securities lending agreements			21,273			1,748			-		-			23,021
Other assets(3)			-			12			-		-			12
Assets of consolidated VIEs:
Bank loans			-			2,004			106		-			2,110
Bonds			-			78			46		-			124
Private / public equity(4)			2			6			22		-			30
Total assets of consolidated VIEs			2			2,088			174		-			2,264
Total		$	117,296		$	42,433		$	855	$	1,231		$	161,815
Liabilities:
Borrowings of consolidated VIEs		$	-		$	-		$	2,402	$	-		$	2,402
Separate account collateral liabilities under securities lending agreements			21,273			1,748			-		-			23,021
Other liabilities(5)			15			5			-		-			20
Total		$	21,288		$	1,753		$	2,402	$	-		$	25,443
	(1)	Amounts are comprised of investments held at cost or amortized cost, carried interest and certain equity method investments, which include investment companies and other assets, which in accordance with GAAP are not accounted for under a fair value measure. In accordance with GAAP, certain equity method investees do not account for both their financial assets and liabilities under fair value measures; therefore, the Company’s investment in such equity method investees may not represent fair value.
	(2)	Level 3 amounts include $212 million and $54 million of underlying third-party private equity funds and direct investments in private equity companies held by private equity funds, respectively.
	(3)	Amount includes company-owned and split-dollar life insurance policies.
	(4)	Level 3 amounts include $20 million and $2 million of underlying third-party private equity funds and direct investments in private equity companies held by a private equity fund.
	(5)	Amounts include a credit default swap (see Note 7, Derivatives and Hedging, for more information) and securities sold short within consolidated sponsored investment funds.
Level 3 Assets.  Level 3 investments of $626 million and $679 million at September 30, 2013 and December 31, 2012, respectively, primarily related to equity method investments and consolidated sponsored investment funds. Level 3 assets within investments, except for direct investments in private equity companies held by private equity funds described below, were primarily valued based upon NAVs received from internal and third-party fund managers.
Direct investments in private equity companies held by private equity funds totaled $34 million and $56 million at September 30, 2013 and December 31, 2012, respectively. Direct investments in private equity companies may be valued using the market approach or the income approach, or a combination thereof, and were valued based on an assessment of each underlying investment, incorporating evaluation of additional significant third-party financing, changes in valuations of comparable peer companies, the business environment of the companies, market indices, assumptions relating to appropriate risk adjustments for nonperformance and legal restrictions on disposition, among other factors. The fair value derived from the methods used is evaluated and weighted, as appropriate, considering the reasonableness of the range of values indicated. Under the market approach, fair value may be determined by reference to multiples of market-comparable companies or transactions, including earnings before interest, taxes, depreciation and amortization (“EBITDA”) multiples. Under the income approach, fair value may be determined by discounting the expected cash flows to a single present value amount using current expectations about those future amounts. Unobservable inputs used in a discounted cash flow model may include projections of operating performance generally covering a five-year period and a terminal value of the private equity direct investment. For securities utilizing the discounted cash flow valuation technique, a significant increase (decrease) in the discount rate, risk premium or discount for lack of marketability in isolation could result in a significantly lower (higher) fair value measurement. For securities utilizing the market comparable companies valuation technique, a significant increase (decrease) in the EBITDA multiple in isolation could result in a significantly higher (lower) fair value measurement.
Level 3 assets recorded within separate account assets include single-broker nonbinding quotes for fixed income securities and equity securities that have unobservable inputs due to certain corporate actions.
Level 3 assets of consolidated VIEs include bank loans and bonds valued based on single-broker non-binding quotes and direct private equity investments and private equity funds valued based upon internal as well as third-party fund manager valuations, which may be adjusted by using the returns of certain market indices.
Level 3 Liabilities.  Level 3 liabilities recorded as borrowings of consolidated VIEs include CLO borrowings valued based upon single-broker non-binding quotes.
Changes in Level 3 Assets and Liabilities Measured at Fair Value on a Recurring Basis for the Three Months Ended September 30, 2013
(in millions)		June 30,			Realized			Purchases		Sales and			Issuances  and			Transfers		Transfers			September 30,		Total net
		2013			and					maturities			other			into		out of			2013		gains (losses)
					unrealized								settlements(1)			Level 3		Level 3					included in
					gains																		earnings(2)
					(losses) in
					earnings
					and OCI
Assets:
Investments
Available-for-sale:
Equity securities (CDOs)			$1			$-			$-		$-			$-			$-		$-			$1		$-
Consolidated sponsored investment funds:
Hedge funds / Funds of funds			47			2			-		(2	)		(2	)		-		-			45		-
Private equity			249			10			-		(23	)		-			-		(2	)		234		7
Equity method:
Hedge funds / Funds of hedge funds			157			1			1		(1	)		(13	)		-		-			145		1
Private equity investments			105			4			1		(10	)		(2	)		-		-			98		4
Real estate funds			97			6			2		-			(2	)		-		-			103		6
Total Level 3 investments			656			23			4		(36	)		(19	)		-		(2	)		626		18
Assets of consolidated VIEs:
Bank loans			93			-			18		(8	)		-			40		(46	)		97
Bonds			35			1			-		(1	)		-			-		-			35
Private equity			19			-			-		(2	)		-			-		-			17
Total Level 3 assets of consolidated VIEs			147			1			18		(11	)		-			40		(46	)		149		n/a	(3)
Total Level 3 assets			$803			$24			$22		($47	)		($19	)		$40		($48	)		$775
Liabilities:
Borrowings of consolidated VIEs			$2,145			($5	)		$-		$-			($82	)		$-		$-			$2,068		n/a	(3)
Other liabilities			-			-			-		-			33			-		-			33
Total Level 3 liabilities			$2,145			($5	)		$-		$-			($49	)		$-		$-			$2,101
	n/a	– not applicable
	(1)	Amounts primarily include distributions from equity method investees, repayments of borrowings of consolidated VIEs and a contingent liability related to the acquisition of Credit Suisse’s ETF franchise.
	(2)	Earnings attributable to the change in unrealized gains (losses) relating to assets still held at the reporting date.
	(3)	The net gain (loss) on consolidated VIEs is solely attributable to noncontrolling interests on the condensed consolidated statements of income.
Changes in Level 3 Assets and Liabilities Measured at Fair Value on a Recurring Basis for the Nine Months Ended September 30, 2013
(in millions)		December 31,			Realized			Purchases		Sales and			Issuances  and			Transfers		Transfers			September 30,		Total net
		2012			and					maturities			other			into		out of			2013		gains
					unrealized								settlements(1)			Level 3		Level 3					(losses)
					gains																		included in
					(losses) in																		earnings(2)
					earnings
					and OCI
Assets:
Investments
Available-for-sale:
Equity securities (CDOs)			$1			$-			$-		$-			$-			$-		$-			$1		$-
Consolidated sponsored investment funds:
Hedge funds / Funds of hedge funds			73			8			12		(11	)		(30	)		-		(7	)		45		6
Private equity			266			26			12		(62	)		-			-		(8	)		234		21
Equity method:
Hedge funds / Funds of hedge funds			161			10			2		(1	)		(27	)		-		-			145		10
Private equity investments			90			14			10		(10	)		(6	)		-		-			98		14
Real estate funds			88			14			5		-			(4	)		-		-			103		14
Total Level 3 investments			679			72			41		(84	)		(67	)		-		(15	)		626		65
Separate account assets			2			-			-		(2	)		-			-		-			-		n/a	(3)
Assets of consolidated VIEs:
Bank loans			106			(1	)		91		(48	)		-			71		(122	)		97
Bonds			46			-			4		(15	)		-			-		-			35
Private equity			22			1			-		(6	)		-			-		-			17
Fund of hedge funds			-			-			134		-			(134	)		-		-			-		-
Total Level 3 assets of consolidated VIEs			174			-			229		(69	)		(134	)		71		(122	)		149		n/a	(4)
Total Level 3 assets			$855			$72			$270		($155	)		($201	)		$71		($137	)		$775
Liabilities:
Borrowings of consolidated VIEs			$2,402			($9	)		$-		$-			($343	)		$-		$-			$2,068		n/a	(4)
Other liabilities			-			-			-		-			33			-		-			33
Total Level 3 liabilities			$2,402			($9	)		$-		$-			($310	)		$-		$-			$2,101
	n/a	– not applicable
	(1)	Amounts primarily include distributions from equity method investees, repayments of borrowings of consolidated VIEs, elimination of investment related to a deconsolidation of a consolidated VIE, a reclassification of an investment from a consolidated sponsored investment fund to an equity method investment due to a change in ownership percentage and a contingent liability related to the acquisition of Credit Suisse’s ETF franchise.
	(2)	Earnings attributable to the change in unrealized gains (losses) relating to assets still held at the reporting date.
	(3)	The net investment income attributable to separate account assets accrues directly to the contract owners and is not reported on the condensed consolidated statements of income.
	(4)	The net gain (loss) on consolidated VIEs is solely attributable to noncontrolling interests on the condensed consolidated statements of income.
Changes in Level 3 Assets and Liabilities Measured at Fair Value on a Recurring Basis for the Three Months Ended September 30, 2012
(in millions)		June 30,			Realized			Purchases		Sales and			Issuances  and			Transfers		Transfers			September 30,		Total net gains
		2012			and					maturities			other			into		out of			2012		(losses)
					unrealized								settlements(1)			Level 3		Level 3					included in
					gains																		earnings(2)
					(losses) in
					earnings
					and OCI
Assets:
Investments
Available-for-sale:
Equity securities (CDOs)			$1			$-			$-		$-			$-			$-		$-			$1		$-
Consolidated sponsored investment funds:
Hedge funds / Funds of funds			46			8			3		(2	)		-			-		-			55		8
Private equity			298			22			-		(14	)		(8	)		-		-			298		20
Equity method:
Hedge funds / Funds of hedge funds			187			14			-		-			(21	)		-		-			180		14
Private equity investments			88			1			1		-			-			-		-			90		2
Real estate funds			101			6			6		(7	)		(3	)		-		-			103		4
Total Level 3 investments			721			51			10		(23	)		(32	)		-		-			727		48
Separate account assets			7			(4	)		6		(7	)		-			34		-			36		n/a	(3)
Assets of consolidated VIEs:
Bank loans			85			2			7		(24	)		7			36		(24	)		89
Bonds			44			1			-		-			-			-		-			45
Private equity			25			2			2		(3	)		-			-		-			26
Total Level 3 assets of consolidated VIEs			154			5			9		(27	)		7			36		(24	)		160		n/a	(4)
Total Level 3 assets			$882			$52			$25		($57	)		($25	)		$70		($24	)		$923
Liabilities:
Borrowings of consolidated VIEs			$1,439			($27	)		$-		$-			$377			$-		$-			$1,843		n/a	(4)
	n/a	– not applicable
	(1)	Amount primarily includes distributions from equity method investees, repayments of borrowings of consolidated VIEs, and loans and borrowings related to the consolidation of one additional CLO.
	(2)	Earnings attributable to the change in unrealized gains (losses) relating to assets still held at the reporting date.
	(3)	The net investment income attributable to separate account assets accrues directly to the contract owners and is not reported on the condensed consolidated statements of income.
	(4)	The net gain (loss) on consolidated VIEs is solely attributable to noncontrolling interests on the condensed consolidated statements of income.
Changes in Level 3 Assets and Liabilities Measured at Fair Value on a Recurring Basis for the Nine Months Ended September 30, 2012
(in millions)		December 31,			Realized			Purchases		Sales and			Issuances  and			Transfers		Transfers			September 30,		Total net gains
		2011			and					maturities			other			into		out of			2012		(losses)
					unrealized								settlements(1)			Level 3		Level 3					included in
					gains																		earnings(2)
					(losses) in
					earnings
					and OCI
Assets:
Investments
Available-for-sale:
Equity securities (CDOs)			$1			$-			$-		$-			$-			$-		$-			$1		$-
Consolidated sponsored investment funds:
Hedge funds / Funds of funds			22			4			30		(2	)		(2	)		3		-			55		4
Private equity			313			43			2		(46	)		(8	)		-		(6	)		298		38
Equity method:
Hedge funds / Funds of hedge funds			193			33			-		-			(46	)		-		-			180		33
Private equity investments			85			7			4		-			(6	)		-		-			90		8
Real estate funds			88			8			19		(7	)		(5	)		-		-			103		6
Total Level 3 investments			702			95			55		(55	)		(67	)		3		(6	)		727		89
Separate account assets			10			(5	)		10		(18	)		-			48		(9	)		36		n/a	(3)
Assets of consolidated VIEs:
Bank loans			83			2			25		(31	)		7			89		(86	)		89
Bonds			40			3			2		-			-			-		-			45
Private equity			27			4			2		(7	)		-			-		-			26
Total Level 3 assets of consolidated VIEs			150			9			29		(38	)		7			89		(86	)		160		n/a	(4)
Total Level 3 assets			$862			$99			$94		($111	)		($60	)		$140		($101	)		$923
Liabilities:
Borrowings of consolidated VIEs			$1,574			($66	)		$-		$-			$203			$-		$-			$1,843		n/a	(4)
	n/a	– not applicable
	(1)	Amount primarily includes distributions from equity method investees, repayments of borrowings of consolidated VIEs, and loans and borrowings related to the consolidation of one additional CLO.
	(2)	Earnings attributable to the change in unrealized gains (losses) relating to assets still held at the reporting date.
	(3)	The net investment income attributable to separate account assets accrues directly to the contract owners and is not reported on the condensed consolidated statements of income.
	(4)	The net gain (loss) on consolidated VIEs is solely attributable to noncontrolling interests on the condensed consolidated statements of income.
Realized and Unrealized Gains (Losses) for Level 3 Assets and Liabilities. Realized and unrealized gains (losses) recorded for Level 3 assets and liabilities are reported in nonoperating income (expense) on the condensed consolidated statements of income. A portion of net income (loss) for consolidated investments and all of the net income (loss) for consolidated VIEs are allocated to noncontrolling interests to reflect net income (loss) not attributable to the Company.
Transfers in and/or out of Levels. Transfers in and/or out of levels are reflected when significant inputs, including market inputs or performance attributes, used for the fair value measurement become observable/unobservable, or when the Company determines it has the ability, or no longer has the ability, to redeem, in the near term, certain investments that the Company values using a NAV (or a capital account), or when the book value of certain equity method investments no longer represents fair value as determined under valuation methodologies.
Separate Account Assets.    During the three and nine months ended September 30, 2012, there were $34 million and $48 million, respectively, of transfers of equity securities into Level 3 from Level 1, primarily due to market inputs no longer being considered observable.
Assets of Consolidated VIEs.    During the three and nine months ended September 30, 2013, there were $46 million and $122 million, respectively, of transfers out of Level 3 to Level 2 related to bank loans. In addition, during the three and nine months ended September 30, 2013, there were $40 million and $71 million, respectively, of transfers into Level 3 from Level 2 related to bank loans. These transfers in and out of Levels 2 and 3 were primarily due to availability/unavailability of observable market inputs, including inputs from pricing vendors and brokers.
During the three and nine months ended September 30, 2012, there were $24 million and $86 million, respectively, of transfers out of Level 3 into Level 2 related to bank loans. In addition, during the three and nine months ended September 30, 2012, there were $36 million and $89 million, respectively, of transfers into Level 3 from Level 2 related to bank loans. These transfers in and out of Levels 2 and 3 were primarily due to availability/unavailability of observable market inputs, including inputs from pricing vendors and brokers.
Consolidated Sponsored Investment Funds.    During the nine months ended September 30, 2013, there were $12 million of transfers out of Level 1 to Level 2 related to consolidated private equity funds. This transfer was due to a direct investment in a public company valued at a discount due to restrictions on sale.
Other Significant Settlements.    During the three and nine months ended September 30, 2013, there were $17 million and $37 million, respectively, of distributions from equity method investees categorized in Level 3.
During the nine months ended September 30, 2013, other settlements included $134 million related to a deconsolidation of a consolidated fund of hedge funds, which was previously classified as a VIE. This fund was deconsolidated during the second quarter 2013 due to the granting of additional substantive rights to unaffiliated investors of the fund.
In addition, during the nine months ended September 30, 2013, there was a $28 million reclassification of a Level 3 investment from a consolidated sponsored investment fund to an equity method investment due to a change in BlackRock’s ownership percentage.
During the three and nine months ended September 30, 2012, there were $24 million and $57 million, respectively, of distributions from equity method investees categorized in Level 3.
In addition, during the three and nine months ended September 30, 2012, other settlements included $406 million of borrowings related to the consolidation of one additional CLO.
Disclosures of Fair Value for Financial Instruments Not Held at Fair Value. At September 30, 2013 and December 31, 2012, the fair value of the Company’s financial instruments not held at fair value are categorized in the table below:
		September 30, 2013						December 31, 2012
(in millions)		Carrying			Estimated			Carrying		Estimated			Fair Value
		Amount			Fair Value			Amount		Fair Value			Hierarchy
Financial Assets:
Cash and cash equivalents		$	3,987		$	3,987		$	4,606	$	4,606			Level 1	(1)
Accounts receivable			4,311			4,311			2,250		2,250			Level 1	(2)
Cash and cash equivalents of consolidated VIEs			93			93			297		297			Level 1	(1)
Financial Liabilities:
Accounts payable and accrued liabilities			3,322			3,322			1,055		1,055			Level 1	(2)
Short-term borrowings			-			-			100		100			Level 1	(2)
Long-term borrowings			4,938			5,310			5,687		6,275			Level 2	(3)
	(1)	Cash and cash equivalents are carried at either cost or amortized cost that approximates fair value due to their short-term maturities. At September 30, 2013 and December 31, 2012, approximately $76 million and $98 million, respectively, of money market funds were recorded within cash and cash equivalents on the condensed consolidated statements of financial condition. Money market funds are valued based on quoted market prices, or $1.00 per share, which generally is the NAV of the fund. At September 30, 2013 and December 31, 2012, approximately $105 million and $133 million, respectively, related to cash and cash equivalents held by consolidated sponsored investment funds.
	(2)	The carrying amounts of accounts receivable, accounts payable and accrued liabilities and short-term borrowings approximate fair value due to their short-term nature.
	(3)	Long-term borrowings are recorded at amortized cost. The fair value of the long-term borrowings, including the current portion of long-term borrowings, is estimated using market prices at the end of September 2013 and December 2012, respectively. See Note 11, Borrowings, for further information on the September 30, 2013 fair value of the Company’s long-term borrowings.
Investments in Certain Entities that Calculate Net Asset Value Per Share
As a practical expedient to value certain investments that do not have a readily determinable fair value and have attributes of an investment company, the Company relies on NAV as the fair value. The following tables list information regarding all investments that use a fair value measurement to account for both their financial assets and financial liabilities in their calculation of a NAV per share (or equivalent).
September 30, 2013
(in millions)		Ref			Fair Value			Total Unfunded		Redemption		Redemption
								Commitments		Frequency		Notice Period
Consolidated sponsored investment funds:
Private equity funds of funds			(a	)		$202			$25	n/r		n/r
Other funds of hedge funds			(b	)		57			-	Monthly (26%),		2 – 90 days
										Quarterly (2%),
										n/r (72%)
Equity method:(1)
Hedge funds/funds of hedge funds			(c	)		212			92	Monthly (2%), Quarterly (32%)		15 – 90 days
										n/r (66%)
Private equity funds			(d	)		98			57	n/r		n/r
Real estate funds			(e	)		123			11	Quarterly (16%)		60 days
										n/r (84%)
Deferred compensation plan hedge fund investments			(f	)		11			-	Monthly (27%), Quarterly (73%)		60 – 90 days
Consolidated VIEs:
Private equity fund			(g	)		15			1	n/r		n/r
Total						$718			$186
	n/r	– not redeemable
	(1)	Comprised of equity method investments, which include investment companies, which in accordance with GAAP account for their financial assets and most financial liabilities under fair value measures; therefore, the Company’s investment in such equity method investees approximates fair value.
December 31, 2012
(in millions)		Ref			Fair Value			Total		Redemption		Redemption
								Unfunded		Frequency		Notice Period
								Commitments
Consolidated sponsored investment funds:
Private equity funds of funds			(a	)		$212			$32	n/r		n/r
Other funds of hedge funds			(b	)		98			-	Monthly (22%)		1 – 90 days
										Quarterly (11%)
										n/r (67%)
Equity method:(1)
Hedge funds/funds of hedge funds			(c	)		222			42	Monthly (2%)		15 – 90 days
										Quarterly (28%)
										n/r (70%)
Private equity funds			(d	)		90			135	n/r		n/r
Real estate funds			(e	)		107			15	Quarterly (18%)		60 days
										n/r (82%)
Deferred compensation plan hedge fund investments			(f	)		9			-	Monthly (33%)		60 – 90 days
										Quarterly (67%)
Consolidated VIE:
Private equity funds			(g	)		20			1	n/r		n/r
Trading:
Equity			(h	)		3			-	Daily (100%)		None
Total						$761			$225
	n/r	– not redeemable
	(1)	Comprised of equity method investments, which include investment companies, which in accordance with GAAP account for their financial assets and most financial liabilities under fair value measures; therefore, the Company’s investment in such equity method investees approximates fair value.
	(a)	This category includes the underlying third-party private equity funds within consolidated BlackRock sponsored private equity funds of funds. The fair values of the investments in the third-party funds have been estimated using capital accounts representing the Company’s ownership interest in each fund in the portfolio as well as other performance inputs. These investments are not subject to redemption; however, for certain funds, the Company may sell or transfer its interest, which may need approval by the general partner of the underlying funds. Due to the nature of the investments in this category, the Company reduces its investment by distributions that are received through the realization of the underlying assets of the funds. It is estimated that the underlying assets of these funds will be liquidated over a weighted-average period of approximately seven years at both September 30, 2013 and December 31, 2012. The total remaining unfunded commitments to other third-party funds were $25 million and $32 million at September 30, 2013 and December 31, 2012, respectively. The Company was contractually obligated to fund $30 million at both September 30, 2013 and December 31, 2012 to the consolidated funds.
	(b)	This category includes consolidated funds of hedge funds that invest in multiple strategies to diversify risks. The fair values of the investments have been estimated using the NAV of the fund’s ownership interest in partners’ capital of each fund in the portfolio. Certain of the underlying funds can be redeemed as long as there are no restrictions in place. At September 30, 2013 and December 31, 2012, the underlying funds that are currently restricted from redemptions within one year will be redeemable in approximately 12 to 24 months. This category also includes a consolidated offshore feeder fund that invests in a master fund with multiple alternative investment strategies. The fair value of this investment has been estimated using the NAV of the master offshore fund held by the feeder fund. The investment is currently subject to restrictions in place by the underlying master fund.
	(c)	This category includes hedge funds and funds of hedge funds that invest primarily in equities, fixed income securities, distressed credit and mortgage instruments and other third-party hedge funds. The fair values of the investments have been estimated using the NAV of the Company’s ownership interest in partners’ capital. It was estimated that the investments in the funds that are not subject to redemption will be liquidated over a weighted-average period of approximately four and five years at September 30, 2013 and December 31, 2012, respectively.
	(d)	This category includes several private equity funds that initially invest in nonmarketable securities of private companies, which ultimately may become public in the future. The fair values of these investments have been estimated using capital accounts representing the Company’s ownership interest in the funds as well as other performance inputs. The Company’s investment in each fund is not subject to redemption and is normally returned through distributions as a result of the liquidation of the underlying assets of the private equity funds. It was estimated that the investments in these funds will be liquidated over a weighted-average period of approximately five years at both September 30, 2013 and December 31, 2012.
	(e)	This category includes several real estate funds that invest directly in real estate and real estate related assets. The fair values of the investments have been estimated using capital accounts representing the Company’s ownership interest in the funds. A majority of the Company’s investments are not subject to redemption or are not currently redeemable and is normally returned through distributions as a result of the liquidation of the underlying assets of the real estate funds. It is estimated that the investments in these funds not subject to redemptions will be liquidated over a weighted-average period of approximately seven years at September 30, 2013 and eight years at December 31, 2012.
	(f)	This category includes investments in certain hedge funds that invest in energy and health science related equity securities. The fair values of the investments in this category have been estimated using capital accounts representing the Company’s ownership interest in partners’ capital as well as performance inputs. The investments in these funds will be redeemed upon settlement of certain deferred compensation liabilities.
	(g)	This category includes the underlying third-party private equity funds within one consolidated BlackRock sponsored private equity fund of funds. The fair values of the investments in the third-party funds have been estimated using capital accounts representing the Company’s ownership interest in each fund in the portfolio as well as other performance inputs. These investments are not subject to redemption; however, for certain funds the Company may sell or transfer its interest, which may need approval by the general partner of the underlying third-party funds. Due to the nature of the investments in this category, the Company reduces its investment by distributions that are received through the realization of the underlying assets of the funds. It is estimated that the underlying assets of these funds will be liquidated over a weighted-average period of approximately two years at September 30, 2013 and three years at December 31, 2012. Total remaining unfunded commitments to other third-party funds were $1 million at both September 30, 2013 and December 31, 2012, which commitments are required to be funded by capital contributions from noncontrolling interest holders.
	(h)	This category includes consolidated offshore feeder funds that invest in master funds with multiple equity strategies to diversify risks. The fair values of the investments in this category have been estimated using the NAV of master offshore funds held by the feeder funds. Investments in this category generally can be redeemed at any time, as long as there are no restrictions in place by the underlying master funds.
Fair Value Option.    Upon the initial consolidation of certain CLOs, the Company elected to adopt the fair value option provisions for eligible assets and liabilities, including bank loans and borrowings of the CLOs to mitigate accounting mismatches between the carrying value of the assets and liabilities and to achieve operational simplification. To the extent there is a difference between the change in fair value of the assets and liabilities, the difference will be reflected as net income (loss) attributable to nonredeemable noncontrolling interests on the condensed consolidated statements of income and offset by a change in appropriated retained earnings on the condensed consolidated statements of financial condition.
The following table summarizes information related to those assets and liabilities selected for fair value accounting at September 30, 2013 and December 31, 2012:
(in millions)		September 30,			December 31,
		2013			2012
CLO Bank Loans:
Aggregate principal amounts outstanding			$1,976			$2,124
Fair value			1,964			2,110
Aggregate unpaid principal balance in excess of (less than) fair value			$12			$14
Unpaid principal balance of loans more than 90 days past due			$12			$4
Aggregate fair value of loans more than 90 days past due			7			-
Aggregate unpaid principal balance in excess of fair value for loans more than 90 days past due			$5			$4
CLO Borrowings:
Aggregate principal amounts outstanding			$2,201			$2,535
Fair value			$2,068			$2,402
At September 30, 2013, the principal amounts outstanding of the borrowings issued by the CLOs mature between 2016 and 2025.
During the three months ended September 30, 2013 and 2012, the change in fair value of the bank loans and bonds held by the CLOs resulted in a $25 million and a $45 million gain, respectively, which were offset by a $28 million and a $44 million loss, respectively, from the change in fair value of the CLO borrowings.
During the nine months ended September 30, 2013 and 2012, the change in fair value of the bank loans and bonds held by the CLOs resulted in a $104 million and a $123 million gain, respectively, which were offset by a $92 million and a $118 million loss, respectively, from the change in fair value of the CLO borrowings.
The net gains (losses) were recorded in net gain (loss) on consolidated VIEs on the condensed consolidated statements of income.
The change in fair value of the assets and liabilities included interest income and expense, respectively.

Variable_Interest_Entities

Variable Interest Entities	9 Months Ended
	Sep. 30, 2013
Text Block [Abstract]	'
Variable Interest Entities	'
	6.  Variable Interest Entities
	In the normal course of business, the Company is the manager of various types of sponsored investment vehicles, including collateralized debt obligations (“CDOs”)/CLOs and sponsored investment funds, which may be considered VIEs. The Company receives advisory fees and/or other incentive-related fees for its services and may from time to time own equity or debt securities or enter into derivatives with the vehicles, each of which are considered variable interests. The Company enters into these variable interests principally to address client needs through the launch of such investment vehicles. The VIEs are primarily financed via capital contributed by equity and debt holders. The Company’s involvement in financing the operations of the VIEs is generally limited to its equity interests.
	The primary beneficiary (“PB”) of a VIE that is an investment fund that meets the conditions of ASU 2010-10, Amendments to Statement 167 for Certain Investment Funds (“ASU 2010-10”), is the enterprise that has a variable interest (or combination of variable interests, including those of related parties) that will absorb a majority of the entity’s expected losses, receive a majority of the entity’s expected residual returns or both. In order to determine whether the Company is the PB of a VIE, management must make significant estimates and assumptions of probable future cash flows of the VIEs. Assumptions made in such analyses may include, but are not limited to, market prices of securities, market interest rates, potential credit defaults on individual securities or default rates on a portfolio of securities, pre-payments, realization of gains, liquidity or marketability of certain securities, discount rates and the probability of certain other outcomes.
	The PB of a CDO/CLO or other entity that is a VIE that does not meet the conditions of ASU 2010-10 is the enterprise that has the power to direct activities of the entity that most significantly impact the entity’s economic performance and has the obligation to absorb losses or the right to receive benefits that potentially could be significant to the entity.
	Consolidated VIEs. Consolidated VIEs included CLOs in which BlackRock did not have an investment; however, BlackRock, as the collateral manager, was deemed to have both the power to control the activities of the CLOs and the right to receive benefits that could potentially be significant to the CLOs. In addition, BlackRock was the PB of one investment fund because it absorbed the majority of the variability due to its de facto third-party relationships with other partners in the fund. The assets of these VIEs are not available to creditors of the Company. In addition, the investors in these VIEs have no recourse to the credit of the Company. At September 30, 2013 and December 31, 2012, the following balances related to VIEs were consolidated on the condensed consolidated statements of financial condition:
	(in millions)		September 30, 2013		December 31, 2012
	Assets of consolidated VIEs:
	Cash and cash equivalents			$93		$297
	Bank loans			1,964		2,110
	Bonds			99		124
	Other investments and other assets			44		30
	Total bank loans, bonds, other investments and other assets			2,107		2,264
	Liabilities of consolidated VIEs:
	Borrowings			-2,068		-2,402
	Other liabilities			-88		-103
	Appropriated retained earnings			-25		-29
	Noncontrolling interests of consolidated VIEs			-19		-27
	Total BlackRock net interests in consolidated VIEs			$-		$-
	For the three months ended September 30, 2013 and 2012, the Company recorded a nonoperating loss of $6 million and a nonoperating gain of $2 million, respectively, offset by a $6 million net loss attributable to nonredeemable noncontrolling interests and a $2 million net gain attributable to nonredeemable noncontrolling interests, respectively, on the condensed consolidated statements of income.
	For the nine months ended September 30, 2013 and 2012, the Company recorded a nonoperating loss of $2 million and a nonoperating gain of $1 million, respectively, offset by a $2 million net loss attributable to nonredeemable noncontrolling interests and a $1 million net gain attributable to nonredeemable noncontrolling interests, respectively, on the condensed consolidated statements of income.
	At September 30, 2013 and December 31, 2012, the weighted-average maturities of the bank loans and bonds attributable to consolidated VIEs were approximately 4.7 and 4.5 years, respectively.
	Non-Consolidated VIEs.    At September 30, 2013 and December 31, 2012, the Company’s carrying value of assets and liabilities and its maximum risk of loss related to VIEs for which it was the sponsor or in which it held a variable interest, but for which it was not the PB, was as follows:
	(in millions)		Variable Interests on the Condensed
			Consolidated
			Statement of Financial Condition
	At September 30, 2013		Investments		Advisory		Other Net		Maximum
					Fee		Assets		Risk of Loss (1)
					Receivables		(Liabilities)
	CDOs/CLOs			$1		$1		($4)		$19
	Other sponsored investment funds:
	Collective trusts			-		166		-		166
	Other			18		130		-5		148
	Total			$19		$297		($9)		$333
	At December 31, 2012
	CDOs/CLOs			$1		$1		($5)		$19
	Other sponsored investment funds:
	Collective trusts			-		248		-		248
	Other			17		61		-3		77
	Total			$18		$310		($8)		$344
	(1)	At both September 30, 2013 and December 31, 2012, BlackRock’s maximum risk of loss associated with these VIEs primarily related to: (i) advisory fee receivables; (ii) BlackRock’s investments; and (iii) $17 million of credit protection sold by BlackRock to a third party in a synthetic CDO transaction.
	The net assets related to the above CDOs/CLOs and other sponsored investment funds, including collective trusts, that the Company does not consolidate were as follows:
	CDOs/CLOs
	(in billions)		September 30, 2013		December 31, 2012
	Assets at fair value			$3		$4
	Liabilities(1)			5		5
	Net assets			($2)		($1)
	(1)	Amounts primarily comprised of unpaid principal debt obligations to CDO/CLO debt holders.
	Other sponsored investments funds. Net assets of other sponsored investment funds that are nonconsolidated VIEs approximated $1.6 trillion to $1.7 trillion at September 30, 2013 and $1.5 trillion to $1.6 trillion at December 31, 2012. Net assets included $1.4 trillion of collective trusts at September 30, 2013 and $1.3 trillion of collective trusts at December 31, 2012. Each collective trust has been aggregated separately and may include collective trusts that invest in other collective trusts. The net assets of these VIEs primarily are comprised of cash and cash equivalents and investments offset by liabilities primarily comprised of various accruals for the sponsored investment vehicles.

Derivatives_and_Hedging

Derivatives and Hedging	9 Months Ended
	Sep. 30, 2013
Derivative Instruments And Hedging Activities Disclosure [Abstract]	'
Derivatives and Hedging	'
	7.  Derivatives and Hedging
	The Company maintains a program to enter into swaps to hedge against market price and interest rate exposures with respect to certain seed investments in sponsored investment products. At September 30, 2013, the Company had outstanding total return swaps and outstanding interest rate swaps with an aggregate notional value of approximately $113 million and $68 million, respectively. At December 31, 2012, the Company had outstanding total return swaps with an aggregate notional value of approximately $206 million.
	The Company executes forward foreign currency exchange contracts to mitigate the risk of foreign exchange risk movements. At September 30, 2013 and December 31, 2012, the Company had outstanding forward foreign currency exchange contracts with an aggregate notional value of approximately $680 million and $79 million, respectively.
	The Company entered into a credit default swap, providing credit protection to a counterparty of approximately $17 million, representing the Company’s maximum risk of loss with respect to the provision of credit protection. The Company carries the credit default swap at fair value based on the expected future cash flows under the arrangement.
	The fair values of the outstanding total return swaps, interest rate swaps, forward foreign currency exchange contracts and the credit default swap were not material to the condensed consolidated statements of financial condition at September 30, 2013 and December 31, 2012.
	Gains (losses) on the total return swaps, interest rate swaps, forward foreign currency exchange contracts and the credit default swap were not material to the condensed consolidated statements of income for the three and nine months ended September 30, 2013 and 2012.
	The Company consolidates certain sponsored investment funds, which may utilize derivative instruments as a part of the funds’ investment strategies. The fair value of such derivatives at September 30, 2013 and December 31, 2012 was not material. The change in fair value of such derivatives, which is recorded in nonoperating income (expense), was not material for the three and nine months ended September 30, 2013 and 2012.
	In May 2011, the Company entered into a designated cash flow hedge consisting of a $750 million interest rate swap to hedge future cash flows on the Company’s floating rate notes due in 2013. Interest on this swap was at a fixed rate of 1.03%, payable semi-annually on May 24 and November 24 of each year. During the second quarter 2013, the interest rate swap matured and the floating rate notes were fully repaid. Gains (losses) on the interest rate swap were not material to the condensed consolidated statements of income for the nine months ended September 30, 2013 and the three and nine months ended September 30, 2012.

Goodwill

Goodwill	9 Months Ended
	Sep. 30, 2013
Goodwill And Intangible Assets Disclosure [Abstract]	'
Goodwill	'
	8.  Goodwill
	Goodwill activity during the nine months ended September 30, 2013 was as follows:
	(in millions)
	December 31, 2012		$12,910
	Acquisition (1)		44
	Goodwill adjustment related to Quellos and other (2)		(16	)
	September 30, 2013		$12,938
	-1	Amount represents goodwill from the Company’s acquisition of Credit Suisse’s ETF franchise on July 1, 2013 for approximately $273 million (the “Credit Suisse ETF Transaction”).
	(2)	The decrease in goodwill during the nine months ended September 30, 2013 primarily resulted from a decline related to tax benefits realized from tax-deductible goodwill in excess of book goodwill from the acquisition of the fund-of-funds business of Quellos Group, LLC in October 2007 (the “Quellos Transaction”). Goodwill related to the Quellos Transaction will continue to be reduced in future periods by the amount of tax benefits realized from tax-deductible goodwill in excess of book goodwill from the Quellos Transaction. The balance of the Quellos tax-deductible goodwill in excess of book goodwill was approximately $301 million and $324 million at September 30, 2013 and December 31, 2012, respectively.

Intangible_Assets

Intangible Assets	9 Months Ended
	Sep. 30, 2013
Goodwill And Intangible Assets Disclosure [Abstract]	'
Intangible Assets	'
	9.  Intangible Assets
	The carrying amounts of identifiable intangible assets are summarized as follows:
	(in millions)		Indefinite-lived		Finite-lived			Total
			intangible assets		intangible assets			intangible assets
	December 31, 2012			$16,760		$642			$17,402
	Acquisition(1)			231		-			231
	Amortization expense			-		(120	)		(120	)
	September 30, 2013			$16,991		$522			$17,513
	-1	Amount represents indefinite-lived management contracts acquired in the Credit Suisse ETF Transaction.

Other_Assets

Other Assets	9 Months Ended
	Sep. 30, 2013
Deferred Costs Capitalized Prepaid And Other Assets Disclosure [Abstract]	'
Other Assets	'
	10.   Other Assets
	At March 31, 2013, BlackRock held an approximately one-third economic equity interest in Private National Mortgage Acceptance Company, LLC (“PNMAC”), which is accounted for as an equity method investment and is included in other assets on the condensed consolidated statements of financial condition. On May 8, 2013, PennyMac became the sole managing member of PNMAC in connection with an initial public offering of PennyMac (the “PennyMac IPO”). As a result of the PennyMac IPO, BlackRock recorded a noncash, nonoperating pre-tax gain of $39 million related to the carrying value of its equity method investment.
	Subsequent to the PennyMac IPO, the Company contributed 6.1 million units of its PennyMac investment to a new donor advised fund (the “Charitable Contribution”). The fair value of the Charitable Contribution was $124 million and is included in general and administration expenses on the condensed consolidated statements of income. In connection with the Charitable Contribution, the Company also recorded a noncash, nonoperating pre-tax gain of $80 million related to the contributed investment and a tax benefit of approximately $57 million.
	The carrying value and fair value of the Company’s remaining interest (approximately 20% or 16 million units) in PennyMac was approximately $120 million and $292 million, respectively, at September 30, 2013. The fair value of the Company’s interest in PennyMac reflected the PennyMac stock price at September 30, 2013.

Borrowings

Borrowings	9 Months Ended
	Sep. 30, 2013
Debt Disclosure [Abstract]	'
Borrowings	'
	11.  Borrowings
	Short-Term Borrowings
	2013 Revolving Credit Facility.     In March 2013, the Company’s credit facility was amended to extend the maturity date by one year to March 2018 and the amount of the aggregate commitment was increased to $3.990 billion (the “2013 credit facility”). The 2013 credit facility permits the Company to request up to an additional $1.0 billion of borrowing capacity, subject to lender credit approval, increasing the overall size of the 2013 credit facility to an aggregate principal amount not to exceed $4.990 billion. Interest on borrowings outstanding accrues at a rate based on the applicable London Interbank Offered Rate plus a spread. The 2013 credit facility requires the Company not to exceed a maximum leverage ratio (ratio of net debt to earnings before interest, taxes, depreciation and amortization, where net debt equals total debt less unrestricted cash) of 3 to 1, which was satisfied with a ratio of less than 1 to 1 at September 30, 2013. At September 30, 2013, the Company had no amount outstanding under the 2013 credit facility.
	Commercial Paper Program.    In April 2013, BlackRock increased the maximum aggregate amount for which the Company could issue unsecured commercial paper notes (the “CP Notes”) on a private-placement basis up to a maximum aggregate amount outstanding at any time of $3.990 billion. The commercial paper program is currently supported by the 2013 credit facility. At September 30, 2013, BlackRock had no CP Notes outstanding.
	Long-Term Borrowings
	The carrying value and fair value of long-term borrowings determined using market prices at the end of September 2013 included the following:
	(in millions)	Maturity Amount		Unamortized		Carrying Value		Fair Value
				Discount
	3.50% Notes due 2014		$1,000		$-		$1,000		$1,036
	1.375% Notes due 2015		750		-		750		762
	6.25% Notes due 2017		700		-2		698		818
	5.00% Notes due 2019		1,000		-2		998		1,147
	4.25% Notes due 2021		750		-4		746		798
	3.375% Notes due 2022		750		-4		746		749
	Total Long-term Borrowings		$4,950		($12)		$4,938		$5,310
	In May 2013, the Company repaid $750 million of two-year floating rate notes at maturity.
	Long-term borrowings at December 31, 2012 had a carrying value of $5.687 billion and a fair value of $6.275 billion determined using market prices at the end of December 2012.
	See Note 11, Borrowings, in the 2012 Form 10-K for more information.

Commitments_and_Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2013
Commitments And Contingencies Disclosure [Abstract]	'
Commitments and Contingencies	'
	12.  Commitments and Contingencies
	Investment Commitments.    At September 30, 2013, the Company had $216 million of various capital commitments to fund sponsored investment funds, including funds of private equity funds, real estate funds, infrastructure funds, opportunistic funds and distressed credit funds. This amount excludes additional commitments made by consolidated funds of funds to underlying third-party funds as third-party noncontrolling interest holders have the legal obligation to fund the respective commitments of such funds of funds. Generally, the timing of the funding of these commitments is unknown and the commitments are callable on demand at any time prior to the expiration of the commitment. These unfunded commitments are not recorded on the condensed consolidated statements of financial condition. These commitments do not include potential future commitments approved by the Company, but which are not yet legally binding. The Company intends to make additional capital commitments from time to time to fund additional investment products for, and with, its clients.
	Contingencies
	Contingent Payments.    The Company acts as the portfolio manager in a series of credit default swap transactions and has a maximum potential exposure of $17 million under a credit default swap between the Company and the counterparty. See Note 7, Derivatives and Hedging, for further discussion.
	Contingent Payment related to Credit Suisse ETF Transaction.    In connection with the Credit Suisse ETF Transaction, BlackRock is required to make contingent payments annually to Credit Suisse, subject to achieving specified thresholds during a seven year period, subsequent to the acquisition date. The fair value of the contingent payments at September 30, 2013 is not significant to the condensed consolidated statement of financial condition and is included in other liabilities.
	Legal Proceedings.    From time to time, BlackRock receives subpoenas or other requests for information from various U.S. federal, state governmental and domestic and international regulatory authorities in connection with certain industry-wide or other investigations or proceedings. It is BlackRock’s policy to cooperate fully with such inquiries. The Company and certain of its subsidiaries have been named as defendants in various legal actions, including arbitrations and other litigation arising in connection with BlackRock’s activities. Additionally, certain of the investment funds that the Company manages are subject to lawsuits, any of which potentially could harm the investment returns of the applicable fund or result in the Company being liable to the funds for any resulting damages.
	Management, after consultation with legal counsel, currently does not anticipate that the aggregate liability, if any, arising out of regulatory matters or lawsuits will have a material effect on BlackRock’s results of operations, financial position, or cash flows. However, there is no assurance as to whether any such pending or threatened matters will have a material effect on BlackRock’s results of operations, financial position or cash flows in any future reporting period. Due to uncertainties surrounding the outcome of these matters, management cannot reasonably estimate the possible loss or range of loss that may arise from these matters.
	Indemnifications.    In the ordinary course of business or in connection with certain acquisition agreements, BlackRock enters into contracts pursuant to which it may agree to indemnify third parties in certain circumstances. The terms of these indemnities vary from contract to contract
	and the amount of indemnification liability, if any, cannot be determined or is considered remote. Consequently, no liability has been recorded on the condensed consolidated statements of financial condition.
	In connection with securities lending transactions, BlackRock has issued certain indemnifications to certain securities lending clients against potential loss resulting from a borrower’s failure to fulfill its obligations under the securities lending agreement should the value of the collateral pledged by the borrower at the time of default be insufficient to cover the borrower’s obligation under the securities lending agreement. At September 30, 2013, the Company indemnified certain of its clients for their securities lending loan balances of approximately $115 billion. The Company held as agent, cash and securities totaling $121 billion as collateral for indemnified securities on loan at September 30, 2013. The fair value of these indemnifications was not material at September 30, 2013.

StockBased_Compensation

Stock-Based Compensation	9 Months Ended
	Sep. 30, 2013
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]	'
Stock-Based Compensation	'
	13.  Stock-Based Compensation
	Restricted stock and restricted stock units (“RSUs”) activity for the nine months ended September 30, 2013 is summarized below:
	Outstanding at		Restricted		Weighted-
			Stock and		Average
			RSUs		Grant Date
					Fair Value
	31-Dec-12			5,620,835		$197.90
	Granted			1,645,277		$234.69
	Converted			-2,502,869		$204.46
	Forfeited			-70,491		$204.41
	September 30, 2013(1)			4,692,752		$207.20
	(1)	At September 30, 2013, approximately 4.4 million awards are expected to vest and 0.3 million awards have vested but have not been converted.
	The Company values restricted stock and RSUs at their grant-date fair value as measured by BlackRock’s common stock price.
	In January 2013, the Company granted 1,172,381 RSUs to employees as part of annual incentive compensation that vest ratably over three years from the date of grant and 370,812 RSUs to employees that cliff vest 100% on January 31, 2016.
	The intrinsic value of outstanding RSUs was $1.3 billion reflecting a closing stock price of $270.62 at September 30, 2013.
	At September 30, 2013, total unrecognized stock-based compensation expense related to unvested RSUs was $348 million. The unrecognized compensation cost is expected to be recognized over a remaining weighted-average period of 0.9 years.
	Market Performance-based RSUs.
	Market performance-based RSU activity for the nine months ended September 30, 2013 is summarized below:
	Outstanding at		Market		Weighted-
			Performance-		Average
			Based RSUs		Grant Date
					Fair Value
	December 31, 2012			575,532	$	115.03
	Granted			556,581	$	126.76
	September 30, 2013 (1)			1,132,113	$	120.8
	(1)	At September 30, 2013, approximately 1.1 million awards are expected to vest and no awards have vested and have been converted.
	The 556,581 market performance-based RSUs that the Company granted in January 2013 will be funded primarily by shares currently held by PNC (see Long-Term Incentive Plans Funded by PNC below).
	At September 30, 2013, total unrecognized stock-based compensation expense related to unvested market performance-based awards was $96 million. The unrecognized compensation cost is expected to be recognized over a remaining weighted-average period of 2.8 years.
	Long-Term Incentive Plans Funded by PNC.    Under a share surrender agreement, PNC committed to provide up to 4 million shares of BlackRock stock held by PNC, to fund certain BlackRock long-term incentive plans (“LTIP”). The current share surrender agreement commits PNC to provide BlackRock series C nonvoting participating preferred stock to fund the remaining committed shares. As of December 31, 2012, 2.5 million shares had been surrendered by PNC. In January 2013, 0.2 million additional shares were surrendered.
	At September 30, 2013, the remaining shares committed by PNC of 1.3 million were available to fund future long-term incentive awards.
	Stock Options.    Stock option activity for the nine months ended September 30, 2013 is summarized below:
	Outstanding at		Shares Under		Weighted-
			Option		Average
					Exercise
					Price
	December 31, 2012			1,099,909	$	167.76
	Exercised			-85,090	$	167.76
	September 30, 2013			1,014,819	$	167.76
	All options were vested at both September 30, 2013 and December 31, 2012. The aggregate intrinsic value of options exercised during the nine months ended September 30, 2013 was $8.3 million.

Net_Capital_Requirements

Net Capital Requirements	9 Months Ended
	Sep. 30, 2013
Banking And Thrift [Abstract]	'
Net Capital Requirements	'
	14.  Net Capital Requirements
	The Company is required to maintain net capital in certain regulated subsidiaries within a number of jurisdictions, which is partially maintained by retaining cash and cash equivalent investments in those subsidiaries or jurisdictions. As a result, such subsidiaries of the Company may be restricted in their ability to transfer cash between different jurisdictions and to their parents. Additionally, transfers of cash between international jurisdictions, including repatriation to the United States, may have adverse tax consequences that could discourage such transfers.
	Capital Requirements.    At September 30, 2013, the Company was required to maintain approximately $1.1 billion in net capital in certain regulated subsidiaries, including BlackRock Institutional Trust Company, N.A. (a chartered national bank whose powers are limited to trust activities and which is subject to regulatory capital requirements administered by the Office of the Comptroller of the Currency), entities regulated by the Financial Conduct Authority and Prudential Regulation Authority in the United Kingdom and the Company’s broker-dealers. The Company was in compliance with all applicable regulatory net capital requirements.

Accumulated_Other_Comprehensiv

Accumulated Other Comprehensive Income (Loss)	9 Months Ended
	Sep. 30, 2013
Text Block [Abstract]	'
Accumulated Other Comprehensive Income (Loss)	'
	15.  Accumulated Other Comprehensive Income (Loss)
	The following table presents changes in AOCI by component for the three and nine months ended September 30, 2013:
	(in millions)		Unrealized gains			Benefit plans			Foreign			Total (1)
			(losses) on						currency
			available-for-sale						translation
			investments						adjustments
	June 30, 2013			$8			($4	)		($202	)		($198	)
	Other comprehensive income (loss) before reclassifications(2)			2			-			118			120
	Amount reclassified from AOCI(3)			(1	)		-			-			(1	)
	Net other comprehensive income (loss) for the three months ended September 30, 2013			1			-			118			119
	September 30, 2013			$9			($4	)		($84	)		($79	)
	(in millions)		Unrealized gains			Benefit plans			Foreign			Total (1)
			(losses) on						currency
			available-for-sale						translation
			investments						adjustments
	December 31, 2012			$16			($4	)		($71	)		($59	)
	Other comprehensive income (loss) before reclassifications(2)			3			-			(13	)		(10	)
	Amount reclassified from AOCI(3)			(10	)		-			-			(10	)
	Net other comprehensive income (loss) for the nine months ended September 30, 2013			(7	)		-			(13	)		(20	)
	September 30, 2013			$9			($4	)		($84	)		($79	)
	(1)	All amounts are net of tax.
	(2)	The tax benefit (expense) was not material for the three and nine months ended September 30, 2013.
	(3)	The tax benefit (expense) was not material for the three and nine months ended September 30, 2013. The pre-tax amount reclassified from AOCI was included in net gain (loss) on investments on the condensed consolidated statements of income.

Capital_Stock

Capital Stock	9 Months Ended
	Sep. 30, 2013
Equity [Abstract]	'
Capital Stock	'
	16.  Capital Stock
	Nonvoting Participating Preferred Stock.    The Company’s preferred shares authorized, issued and outstanding consisted of the following:
		September 30,		December 31,
		2013		2012
	Series A
	Shares authorized, $0.01 par value		20,000,000		20,000,000
	Shares issued and outstanding		-		-
	Series B
	Shares authorized, $0.01 par value		150,000,000		150,000,000
	Shares issued and outstanding		823,188		823,188
	Series C
	Shares authorized, $0.01 par value		6,000,000		6,000,000
	Shares issued and outstanding		1,311,887		1,517,237
	Series D
	Shares authorized, $0.01 par value		20,000,000		20,000,000
	Shares issued and outstanding		-		-
	Share Repurchase Approval.    In January 2013, the Board of Directors approved an increase in the availability under the Company’s existing share repurchase program to allow for the repurchase of up to 10.2 million shares of BlackRock common stock. The Company repurchased 2.9 million common shares in open market-transactions under the share repurchase program for approximately $750 million during the nine months ended September 30, 2013. At September 30, 2013, there were 7.3 million shares still authorized to be repurchased.

Earnings_Per_Share

Earnings Per Share	9 Months Ended
	Sep. 30, 2013
Earnings Per Share [Abstract]	'
Earnings Per Share	'
	17.  Earnings Per Share
	Prior to the quarter ended March 31, 2013, the Company calculated earnings per share (“EPS”) pursuant to the two-class method as defined in ASC 260-10, Earnings per Share (“ASC 260-10”), which specifies that all outstanding unvested share-based payment awards that contain rights to nonforfeitable dividends or dividend equivalents are considered participating securities and should be included in the computation of EPS pursuant to the two-class method. The majority of the Company’s participating securities vested in January 2013 and, therefore, beginning in the quarter ended March 31, 2013, the Company calculates EPS under the treasury stock method.
	Due to the similarities in terms between BlackRock nonvoting participating preferred stock and the Company’s common stock, the Company considers its participating preferred stock to be a common stock equivalent for purposes of EPS calculations. As such, the Company has included the outstanding nonvoting participating preferred stock in the calculation of average basic and diluted shares outstanding.
	The following table sets forth the computation of basic and diluted EPS for the three and nine months ended September 30, 2013 under the treasury stock method:
	( in millions, except share data)		Three Months		Nine Months
			Ended		Ended
			September 30,		September 30,
			2013		2013
	Net income attributable to BlackRock			$730		$2,091
	Basic weighted-average shares outstanding			169,811,633		170,581,930
	Dilutive effect of nonparticipating RSUs and stock options			3,559,875		3,430,946
	Total diluted weighted-average shares outstanding			173,371,508		174,012,876
	Basic earnings per share			$4.30		$12.26
	Diluted earnings per share			$4.21		$12.02
	The following table sets forth the computation of basic and diluted EPS for the three and nine months ended September 30, 2012 under the two-class method:
	(in millions, except share data)		Three Months		Nine Months
			Ended		Ended
			September 30,		September 30,
			2012		2012
	Net income attributable to BlackRock			$642		$1,768
	Less:
	Dividends distributed to common shares			259		803
	Dividends distributed to participating RSUs			-		1
	Undistributed net income attributable to BlackRock			383		964
	Percentage of undistributed net income allocated to common shares(1)			99.90%		99.90%
	Undistributed net income allocated to common shares			382		963
	Plus:
	Common share dividends			259		803
	Net income attributable to common shares			$641		$1,766
	Basic weighted-average shares outstanding			172,359,141		176,116,975
	Dilutive effect of nonparticipating RSUs and stock options			3,091,391		2,839,724
	Total diluted weighted-average shares outstanding			175,450,532		178,956,699
	Basic earnings per share			$3.72		$10.02
	Diluted earnings per share			$3.65		$9.87
		(1)	Allocation to common stockholders was based on the total of common shares and participating securities (which represent unvested RSUs that contain nonforfeitable rights to dividends). For the three months and nine months ended September 30, 2012, average outstanding participating securities were 0.2 million.

Income_Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2013
Income Tax Disclosure [Abstract]	'
Income Taxes	'
	18. Income Taxes
	The three and nine months ended September 30, 2013 included a $64 million net noncash benefit primarily related to the revaluation of certain deferred income tax liabilities, including legislation enacted in the United Kingdom and domestic state and local income tax changes. In addition, the nine months ended September 30, 2013 included the approximately $57 million tax benefit recognized in connection with the Charitable Contribution and a tax benefit of approximately $29 million, primarily due to the realization of tax loss carryforwards. See Note 10, Other Assets, for more information on the $57 million tax benefit.
	The three and nine months ended September 30, 2012 included a $30 million net noncash benefit related to the revaluation of certain deferred income tax liabilities, including legislation enacted in the United Kingdom, domestic state and local income tax changes, and the tax effect resulting from changes in the Company’s organizational structure.

Segment_Information

Segment Information	9 Months Ended
	Sep. 30, 2013
Segment Reporting [Abstract]	'
Segment Information	'
	19.  Segment Information
	The Company’s management directs BlackRock’s operations as one business, the asset management business. As such, the Company operates in one business segment in accordance with ASC 280-10, Segment Reporting.
	The following table illustrates investment advisory, administration fees, securities lending revenue and performance fees, BlackRock Solutions® and advisory revenue, distribution fees and other revenue for the three and nine months ended September 30, 2013 and 2012, respectively.
		Three Months Ended						Nine Months Ended
		September 30,						September 30,
	(in millions)	2013				2012		2013		2012
	Equity	$	1,170			$	1,073	$	3,525	$	3,196
	Fixed income		490				491		1,488		1,386
	Multi-asset		266				241		777		724
	Alternatives		248				232		718		642
	Cash management		75				90		244		267
	Total investment advisory, administration fees, securities lending revenue and performance fees		2,249				2,127		6,752		6,215
	BlackRock Solutions and advisory		156				128		420		382
	Distribution fees		19				19		54		58
	Other revenue		48				46		177		143
	Total revenue	$	2,472			$	2,320	$	7,403	$	6,798
	The following table illustrates total revenue for the three and nine months ended September 30, 2013 and 2012, respectively, by geographic region. These amounts are aggregated on a legal entity basis and do not necessarily reflect where the customer resides.
	(in millions)	Three Months Ended						Nine Months Ended
		September 30,						September 30,
	Revenue	2013				2012		2013		2012
	Americas	$	1,632			$	1,578	$	4,967	$	4,676
	Europe		726				629		2,060		1,795
	Asia-Pacific		114				113		376		327
	Total revenue	$	2,472			$	2,320	$	7,403	$	6,798
	The following table illustrates long-lived assets that consist of goodwill and property and equipment at September 30, 2013 and December 31, 2012 by geographic region. These amounts are aggregated on a legal entity basis and do not necessarily reflect where the asset is physically located.
	(in millions)			September 30,				December 31,
	Long-lived Assets			2013				2012
	Americas			$	13,197			$	13,238
	Europe				207				166
	Asia-Pacific				57				63
	Total long-lived assets			$	13,461			$	13,467
	Americas primarily is comprised of the United States, Canada, Brazil and Mexico, while Europe is primarily comprised of the United Kingdom. Asia-Pacific is comprised of Japan, Australia, Singapore, Hong Kong, Taiwan, Korea, India, Malaysia and China.

Subsequent_Events

Subsequent Events	9 Months Ended
	Sep. 30, 2013
Subsequent Events [Abstract]	'
Subsequent Events	'
	20. Subsequent Events
	Acquisitions
	MGPA. In October 2013, the Company completed the acquisition of MGPA, an independently managed private equity real estate investment advisory company primarily in Asia and Europe.
	Other
	The Company conducted a review for additional subsequent events and determined that no additional subsequent events had occurred that would require accrual or disclosure.

Significant_Accounting_Policie1

Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2013
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 on the condensed consolidated statements of financial condition include the portion of consolidated sponsored investment funds in which the Company does not have direct equity ownership. Significant accounts and transactions between consolidated entities have been eliminated.
	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 revenues and expenses 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 notes related thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2012, which was filed with the Securities and Exchange Commission (“SEC”) on March 1, 2013 (“2012 Form 10-K”).
	The interim financial information at September 30, 2013 and for the three and nine months ended September 30, 2013 and 2012 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 indicative of results to be expected for the full year.
Fair Value Measurements	'
	Fair Value Measurements.
	Hierarchy of Fair Value Inputs.    The provisions of Accounting Standards Codification (“ASC”) 820-10, Fair Value Measurements and Disclosures (“ASC 820-10”), establish a hierarchy that prioritizes inputs to valuation techniques used to measure fair value and require companies to disclose the fair value of their financial instruments according to the fair value hierarchy (i.e., Level 1, 2 and 3 inputs, as defined). 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 (including those accounted for under the equity method of accounting as these mutual funds are investment companies that have publicly available net asset values (“NAVs”), which in accordance with GAAP, are calculated under fair value measures and the changes in fair values are equal to the earnings of such funds), ETFs, listed equities 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. As a practical expedient, the Company relies on the NAV (or its equivalent) of certain investments as their fair value.
		•	Level 2 assets may include debt securities, bank loans, short-term floating-rate notes and asset-backed securities, securities held within consolidated hedge funds, certain equity method limited partnership interests in hedge funds valued based on NAV (or its equivalent) where the Company has the ability to redeem at the measurement date or within the near term without redemption restrictions, restricted public securities valued at a discount, as well as over-the-counter derivatives, including interest and inflation 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. Certain investments that are valued using a NAV (or its equivalent) and are subject to current redemption restrictions that will not be lifted in the near term are included in Level 3.
		•	Level 3 assets may include general and limited partnership interests in private equity funds, funds of private equity funds, real estate funds, hedge funds and funds of hedge funds, direct private equity investments held within consolidated funds, bank loans and bonds.
		•	Level 3 liabilities include borrowings of consolidated collateralized loan obligations (“CLOs”) valued based upon nonbinding single-broker quotes.
		•	Level 3 inputs include BlackRock capital accounts for its partnership interests in various alternative investments, including distressed credit hedge funds, real estate and private equity funds, which may be adjusted by using the returns of certain market indices.
Significance of Inputs	'
	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 Techniques	'
	Valuation Techniques.    The fair values of certain Level 3 assets and liabilities were determined using various methodologies as appropriate, including NAVs of underlying investments, third-party pricing vendors, broker quotes and market and income approaches. Such quotes and modeled prices are evaluated for reasonableness through various procedures, including due diligence reviews of third-party pricing vendors, variance analyses, consideration of the current market environment and other analytical procedures.
	As a practical expedient, the Company relies on NAV as the fair value for certain investments. The inputs to value these investments may include BlackRock capital accounts for its partnership interests in various alternative investments, including distressed credit hedge funds, real estate 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 may be used as an input to value these investments.
	A significant amount of inputs used to value equity, debt securities and bank loans is sourced from well-recognized 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. Annually, BlackRock’s internal valuation committee or other designated groups review both the valuation methodologies, including the general assumptions and methods used to value various asset classes, and operational processes with these vendors. In addition, on a quarterly basis, meetings are held with the vendors to identify any significant changes to the vendors’ processes.
	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.
Fair Value Option	'Fair Value Option.    ASC 825-10, Financial Instruments (“ASC 825-10”), provides a fair value option election that allows companies an irrevocable election to use fair value as the initial and subsequent accounting measurement attribute for certain financial assets and liabilities. ASC 825-10 permits entities to elect to measure eligible financial assets and liabilities at fair value on an ongoing basis. Unrealized gains and losses on items for which the fair value option has been elected are reported in earnings. The decision to elect the fair value option is determined on an instrument-by-instrument basis, which must be applied to an entire instrument, and not only specified risks, specific cash flows, or portions of that instrument, and is irrevocable once elected. Assets and liabilities measured at fair value pursuant to ASC 825-10 are required to be reported separately from those instruments measured using another accounting method
Derivative Instruments and Hedging Activities	'
	Derivative Instruments and Hedging Activities.    ASC 815-10, Derivatives and Hedging (“ASC 815-10”), establishes accounting and reporting standards for derivative instruments, including certain derivatives embedded in other contracts and for hedging activities. ASC 815-10 generally requires an entity to recognize all derivatives as either assets or liabilities on the condensed consolidated statements of financial condition and to measure those investments at fair value.
	The Company does not use derivative financial instruments for trading or speculative purposes. The Company uses derivative financial instruments primarily for purposes of hedging: (i) exposures to fluctuations in foreign currency exchange rates of certain assets and liabilities, (ii) market exposures for certain seed investments and (iii) future cash flows on floating-rate notes. The Company may also use derivatives within its separate account assets, which are segregated funds held for purposes of funding individual and group pension contracts. In addition, certain consolidated sponsored investment funds may also invest in derivatives as a part of their investment strategy.
	Changes in the fair value of the Company’s derivative financial instruments are generally recognized in earnings and, where applicable, are offset by the corresponding gain or loss on the related foreign-denominated assets or liabilities or hedged investments, on the condensed consolidated statements of income.
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, 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, 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 in accordance with the ASC 944-80, Financial Services – Separate Accounts.
	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 receives collateral with minimum values generally ranging from approximately 102% to 112% of the value of the securities lent 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, in the event of customer default, the right to liquidate collateral or to request additional collateral. Under the Company’s securities lending arrangements, the Company can resell or re-pledge the collateral and the borrower can resell or re-pledge the loaned securities. 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 under ASC 860, Transfers and Servicing.
	As a result of the Company’s ability to resell or re-pledge the collateral, the Company records on the condensed consolidated statements of financial condition the cash and noncash collateral received under these arrangements as its own asset in addition to an equal and offsetting collateral liability for the obligation to return the collateral. During the nine months ended September 30, 2013 and 2012, the Company had not re-sold or re-pledged any of the collateral received under these arrangements. At September 30, 2013 and December 31, 2012, the fair value of loaned securities held by separate account assets was approximately $20.2 billion and $21.0 billion, respectively, and the fair value of the collateral held under these securities lending agreements was approximately $22.0 billion and $23.0 billion, respectively.
Appropriated Retained Earnings	'Appropriated Retained Earnings.    Upon the initial consolidation of CLOs, BlackRock records a cumulative effect adjustment to appropriated retained earnings on the condensed consolidated statements of financial condition equal to the difference between the fair value of the CLOs’ assets and the fair value of their liabilities. Such amounts are recorded as appropriated retained earnings as the CLO noteholders, not BlackRock, ultimately will receive the benefits or absorb the losses associated with the CLOs’ assets and liabilities. The net change in the fair value of the CLOs’ assets and liabilities is recorded as net income (loss) attributable to nonredeemable noncontrolling interests and as an adjustment to appropriated retained earnings.
Amendments to Accumulated Other Comprehensive Income Disclosures	'
	Amendments to Accumulated Other Comprehensive Income Disclosures.    On February 5, 2013, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2013-02, Reporting of Amounts Reclassified Out of Accumulated Other Comprehensive Income (“ASU 2013-02”), which added new disclosure requirements for items reclassified out of accumulated other comprehensive income (“AOCI”). See Note 15, Accumulated Other Comprehensive Income (Loss).
Disclosures About Offsetting Assets and Liabilities	'Disclosures About Offsetting Assets and Liabilities.    On December 16, 2011, the FASB issued ASU 2011-11, Disclosures About Offsetting Assets and Liabilities (“ASU 2011-11”), which created new disclosure requirements about the nature of an entity’s rights of setoff and related arrangements associated with its financial instruments and derivative instruments. On January 31, 2013, the FASB issued ASU 2013-01, Clarifying the Scope of Disclosures about Offsetting Assets and Liabilities (“ASU 2013-01”), that provides clarification about which instruments and transactions are subject to ASU 2011-11. The adoption of ASU 2011-11 and ASU 2013-01 on January 1, 2013 was not material to the condensed consolidated financial statements.
Benchmark Interest Rate for Hedge Accounting	'
	Benchmark Interest Rate for Hedge Accounting.    In July 2013, the FASB issued ASU 2013-10, Inclusion of the Fed Funds Effective Swap Rate (or Overnight Index Swap Rate) as a Benchmark Interest Rate for Hedge Accounting Purposes (“ASU 2013-10”). ASU 2013-10 provides for the inclusion of certain interest rate benchmarks for hedge accounting purposes. The adoption of ASU 2013-10 in the third quarter 2013 did not have a material impact on the condensed consolidated financial statements.

Investments_Tables

Investments (Tables)	9 Months Ended
	Sep. 30, 2013
Investments Debt And Equity Securities [Abstract]	'
Summary of Carrying Value of Investments	'
	A summary of the carrying value of investments is as follows:
	(in millions)		September 30,				December 31,
			2013				2012
	Available-for-sale investments			$168				$158
	Held-to-maturity investments			57				112
	Trading investments:
	Consolidated sponsored investment funds			381				123
	Other equity and debt securities			67				94
	Deferred compensation plan mutual funds			57				53
	Total trading investments			505				270
	Other investments:
	Consolidated sponsored investment funds			314				401
	Equity method investments			564				595
	Deferred compensation plan hedge fund equity method investments			11				9
	Cost method investments(1)			122				120
	Carried interest			137				85
	Total other investments			1,148				1,210
	Total investments			$1,878				$1,750
		(1)	Amounts primarily include Federal Reserve Bank Stock.
Summary of Cost and Carrying Value of Investments Classified as Available-for-Sale	'
	A summary of the cost and carrying value of investments classified as available-for-sale investments is as follows:
	(in millions)
							Gross Unrealized						Carrying
	At September 30, 2013		Cost				Gains				Losses		Value
	Equity securities of sponsored investment funds			$163				$6				($4)		$165
	Other securities			1				2				-		3
	Total available-for-sale investments			$164				$8				($4)		$168
	At December 31, 2012
	Equity securities of sponsored investment funds			$142				$14				($1)		$155
	Other securities			2				1				-		3
	Total available-for-sale investments			$144				$15				($1)		$158
Summary of Cost and Carrying Value of Trading Investments	'
	A summary of the cost and carrying value of trading investments is as follows:
	(in millions)		September 30, 2013						December 31, 2012
			Cost		Carrying				Cost		Carrying
					Value						Value
	Trading investments:
	Deferred compensation plan mutual funds			$  51		$  57				$  46		$  53
	Equity/Multi-asset mutual funds			190		194				154		162
	Debt securities/fixed income mutual funds:
	Corporate debt			126		126				44		44
	Government debt			132		128				11		11
	Total trading investments			$499		$505				$255		$270
Summary of Cost and Carrying Value of Other Investments	'
	A summary of the cost and carrying value of other investments is as follows:
	(in millions)		September 30, 2013						December 31, 2012
			Cost		Carrying				Cost		Carrying
					Value						Value
	Other investments:
	Consolidated sponsored investment funds			$303		$314				$378		$401
	Equity method			480		564				541		595
	Deferred compensation plan hedge fund			9		11				15		9
	equity method investments
	Cost method investments:
	Federal Reserve Bank stock			93		93				89		89
	Other			17		29				31		31
	Total cost method investments			110		122				120		120
	Carried interest			-		137				-		85
	Total other investments			$902		$1,148				$1,054		$1,210

Consolidated_Sponsored_Investm1

Consolidated Sponsored Investment Funds (Tables)	9 Months Ended
	Sep. 30, 2013
Text Block [Abstract]	'
Consolidated Sponsored Investment Funds Included in Condensed Consolidated Statements of Financial Condition	'
	The following table presents the balances related to these consolidated funds that were included on the condensed consolidated statements of financial condition as well as BlackRock’s net interest in these funds:
	(in millions)	September 30,		December 31,
		2013		2012
	Cash and cash equivalents		$105		$133
	Investments:
	Trading investments		381		123
	Other investments		314		401
	Other assets		13		25
	Other liabilities		-33		-65
	Noncontrolling interests		-168		-187
	BlackRock’s net interests in consolidated sponsored investment funds		$612		$430

Fair_Value_Disclosures_Tables

Fair Value Disclosures (Tables)	9 Months Ended
	Sep. 30, 2013
Fair Value Disclosures [Abstract]	'
Assets and Liabilities Measured at Fair Value on Recurring Basis	'
	Assets and liabilities measured at fair value on a recurring basis and other assets not held at fair value
	September 30, 2013		Quoted			Significant Other			Significant		Other Assets			September 30,
	(in millions)		Prices in			Observable Inputs			Unobservable		Not Held at Fair			2013
			Active			(Level 2)			Inputs		Value(1)
			Markets for						(Level 3)
			Identical
			Assets
			(Level 1)
	Assets:
	Investments
	Available-for-sale:
	Equity securities (funds and CDOs)		$	165		$	-		$	1	$	-		$	166
	Debt securities			-			2			-		-			2
	Total available-for-sale			165			2			1		-			168
	Held-to-maturity debt securities			-			-			-		57			57
	Trading:
	Deferred compensation plan mutual funds			57			-			-		-			57
	Equity/Multi-asset mutual funds			194			-			-		-			194
	Debt securities / fixed income mutual funds			61			193			-		-			254
	Total trading			312			193			-		-			505
	Other investments:
	Consolidated sponsored investment funds:
	Hedge funds / Funds of funds			1			21			45		-			67
	Private / public equity(2)			5			8			234		-			247
	Total consolidated sponsored investment funds			6			29			279		-			314
	Equity method:
	Hedge funds / Funds of hedge funds			-			67			145		55			267
	Private equity investments			-			-			98		-			98
	Real estate funds			-			20			103		7			130
	Fixed income mutual funds			63			-			-		-			63
	Equity/Multi-asset, alternative mutual funds			6			-			-		-			6
	Total equity method			69			87			346		62			564
	Deferred compensation plan hedge fund equity method investments			-			11			-		-			11
	Cost method investments			-			-			-		122			122
	Carried interest			-			-			-		137			137
	Total investments			552			322			626		378			1,878
	Separate account assets			106,085			39,675			-		886			146,646
	Separate account collateral held under securities lending agreements:
	Equity securities			19,851			-			-		-			19,851
	Debt securities			-			2,111			-		-			2,111
	Total separate account collateral held under securities lending agreements			19,851			2,111			-		-			21,962
	Other assets(3)			-			12			-		-			12
	Assets of consolidated VIEs:
	Bank loans and other assets			-			1,867			97		20			1,984
	Bonds			-			64			35		-			99
	Private / public equity(4)			-			7			17		-			24
	Total assets of consolidated VIEs			-			1,938			149		20			2,107
	Total		$	126,488		$	44,058		$	775	$	1,284		$	172,605
	Liabilities:
	Borrowings of consolidated VIEs		$	-		$	-		$	2,068	$	-		$	2,068
	Separate account collateral liabilities under securities lending agreements			19,851			2,111			-		-			21,962
	Other liabilities(5)			19			4			33		-			56
	Total		$	19,870		$	2,115		$	2,101	$	-		$	24,086
		(1)	Amounts are comprised of investments held at cost or amortized cost, carried interest and certain equity method investments, which include investment companies and other assets, which in accordance with GAAP are not accounted for under a fair value measure. In accordance with GAAP, certain equity method investees do not account for both their financial assets and liabilities under fair value measures; therefore, the Company’s investment in such equity method investees may not represent fair value.
		(2)	Level 3 amounts include $202 million and $32 million of underlying third-party private equity funds and direct investments in private equity companies held by private equity funds, respectively.
		(3)	Amount includes company-owned and split-dollar life insurance policies.
		(4)	Level 3 amounts include $15 million and $2 million of underlying third-party private equity funds and direct investments in private equity companies held by a private equity fund.
		(5)	Amounts include a credit default swap (see Note 7, Derivatives and Hedging, for more information), securities sold short within consolidated sponsored investment funds and a contingent liability related to the acquisition of Credit Suisse’s ETF franchise.
	Assets and liabilities measured at fair value on a recurring basis and other assets not held at fair value
	December 31, 2012		Quoted			Significant			Significant		Other Assets			December 31,
	(in millions)		Prices in			Other			Unobservable		Not Held at			2012
			Active			Observable			Inputs		Fair Value (1)
			Markets for			Inputs			(Level 3)
	Identical		(Level 2)
	Assets
	(Level 1)
Assets:
Investments
Available-for-sale:
Equity securities (funds and CDOs)		$	155		$	-		$	1	$	-		$	156
Debt securities			-			2			-		-			2
Total available-for-sale			155			2			1		-			158
Held-to-maturity debt securities			-			-			-		112			112
Trading:
Deferred compensation plan mutual funds			53			-			-		-			53
Equity/Multi-asset mutual funds			159			3			-		-			162
Debt securities / fixed income mutual funds			5			50			-		-			55
Total trading			217			53			-		-			270
Other investments:
Consolidated sponsored investment funds:
Hedge funds / Funds of funds			3			39			73		-			115
Private / public equity(2)			10			10			266		-			286
Total consolidated sponsored investment funds			13			49			339		-			401
Equity method:
Hedge funds / Funds of hedge funds			-			61			161		39			261
Private equity investments			-			-			90		-			90
Real estate funds			-			19			88		15			122
Fixed income mutual funds			46			-			-		-			46
Equity/Multi-asset, alternative mutual funds			76			-			-		-			76
Total equity method			122			80			339		54			595
Deferred compensation plan hedge fund equity method investments			-			9			-		-			9
Cost method investments			-			-			-		120			120
Carried interest			-			-			-		85			85
Total investments			507			193			679		371			1,750
Separate account assets			95,514			38,392			2		860			134,768
Separate account collateral held under securities lending agreements:
Equity securities			21,273			-			-		-			21,273
Debt securities			-			1,748			-		-			1,748
Total separate account collateral held under securities lending agreements			21,273			1,748			-		-			23,021
Other assets(3)			-			12			-		-			12
Assets of consolidated VIEs:
Bank loans			-			2,004			106		-			2,110
Bonds			-			78			46		-			124
Private / public equity(4)			2			6			22		-			30
Total assets of consolidated VIEs			2			2,088			174		-			2,264
Total		$	117,296		$	42,433		$	855	$	1,231		$	161,815
Liabilities:
Borrowings of consolidated VIEs		$	-		$	-		$	2,402	$	-		$	2,402
Separate account collateral liabilities under securities lending agreements			21,273			1,748			-		-			23,021
Other liabilities(5)			15			5			-		-			20
Total		$	21,288		$	1,753		$	2,402	$	-		$	25,443
	(1)	Amounts are comprised of investments held at cost or amortized cost, carried interest and certain equity method investments, which include investment companies and other assets, which in accordance with GAAP are not accounted for under a fair value measure. In accordance with GAAP, certain equity method investees do not account for both their financial assets and liabilities under fair value measures; therefore, the Company’s investment in such equity method investees may not represent fair value.
	(2)	Level 3 amounts include $212 million and $54 million of underlying third-party private equity funds and direct investments in private equity companies held by private equity funds, respectively.
	(3)	Amount includes company-owned and split-dollar life insurance policies.
	(4)	Level 3 amounts include $20 million and $2 million of underlying third-party private equity funds and direct investments in private equity companies held by a private equity fund.
	(5)	Amounts include a credit default swap (see Note 7, Derivatives and Hedging, for more information) and securities sold short within consolidated sponsored investment funds.
Changes in Level 3 Assets and Liabilities Measured at Fair Value on Recurring Basis	'
	Changes in Level 3 Assets and Liabilities Measured at Fair Value on a Recurring Basis for the Three Months Ended September 30, 2013
	(in millions)		June 30,			Realized			Purchases		Sales and			Issuances  and			Transfers		Transfers			September 30,		Total net
			2013			and					maturities			other			into		out of			2013		gains (losses)
						unrealized								settlements(1)			Level 3		Level 3					included in
						gains																		earnings(2)
						(losses) in
						earnings
						and OCI
	Assets:
	Investments
	Available-for-sale:
	Equity securities (CDOs)			$1			$-			$-		$-			$-			$-		$-			$1		$-
	Consolidated sponsored investment funds:
	Hedge funds / Funds of funds			47			2			-		(2	)		(2	)		-		-			45		-
	Private equity			249			10			-		(23	)		-			-		(2	)		234		7
	Equity method:
	Hedge funds / Funds of hedge funds			157			1			1		(1	)		(13	)		-		-			145		1
	Private equity investments			105			4			1		(10	)		(2	)		-		-			98		4
	Real estate funds			97			6			2		-			(2	)		-		-			103		6
	Total Level 3 investments			656			23			4		(36	)		(19	)		-		(2	)		626		18
	Assets of consolidated VIEs:
	Bank loans			93			-			18		(8	)		-			40		(46	)		97
	Bonds			35			1			-		(1	)		-			-		-			35
	Private equity			19			-			-		(2	)		-			-		-			17
	Total Level 3 assets of consolidated VIEs			147			1			18		(11	)		-			40		(46	)		149		n/a	(3)
	Total Level 3 assets			$803			$24			$22		($47	)		($19	)		$40		($48	)		$775
	Liabilities:
	Borrowings of consolidated VIEs			$2,145			($5	)		$-		$-			($82	)		$-		$-			$2,068		n/a	(3)
	Other liabilities			-			-			-		-			33			-		-			33
	Total Level 3 liabilities			$2,145			($5	)		$-		$-			($49	)		$-		$-			$2,101
		n/a	– not applicable
		(1)	Amounts primarily include distributions from equity method investees, repayments of borrowings of consolidated VIEs and a contingent liability related to the acquisition of Credit Suisse’s ETF franchise.
		(2)	Earnings attributable to the change in unrealized gains (losses) relating to assets still held at the reporting date.
		(3)	The net gain (loss) on consolidated VIEs is solely attributable to noncontrolling interests on the condensed consolidated statements of income.
	Changes in Level 3 Assets and Liabilities Measured at Fair Value on a Recurring Basis for the Nine Months Ended September 30, 2013
	(in millions)		December 31,			Realized			Purchases		Sales and			Issuances  and			Transfers		Transfers			September 30,		Total net
			2012			and					maturities			other			into		out of			2013		gains
						unrealized								settlements(1)			Level 3		Level 3					(losses)
						gains																		included in
						(losses) in																		earnings(2)
						earnings
						and OCI
	Assets:
	Investments
	Available-for-sale:
	Equity securities (CDOs)			$1			$-			$-		$-			$-			$-		$-			$1		$-
	Consolidated sponsored investment funds:
	Hedge funds / Funds of hedge funds			73			8			12		(11	)		(30	)		-		(7	)		45		6
	Private equity			266			26			12		(62	)		-			-		(8	)		234		21
	Equity method:
	Hedge funds / Funds of hedge funds			161			10			2		(1	)		(27	)		-		-			145		10
	Private equity investments			90			14			10		(10	)		(6	)		-		-			98		14
	Real estate funds			88			14			5		-			(4	)		-		-			103		14
	Total Level 3 investments			679			72			41		(84	)		(67	)		-		(15	)		626		65
	Separate account assets			2			-			-		(2	)		-			-		-			-		n/a	(3)
	Assets of consolidated VIEs:
	Bank loans			106			(1	)		91		(48	)		-			71		(122	)		97
	Bonds			46			-			4		(15	)		-			-		-			35
	Private equity			22			1			-		(6	)		-			-		-			17
	Fund of hedge funds			-			-			134		-			(134	)		-		-			-		-
	Total Level 3 assets of consolidated VIEs			174			-			229		(69	)		(134	)		71		(122	)		149		n/a	(4)
	Total Level 3 assets			$855			$72			$270		($155	)		($201	)		$71		($137	)		$775
	Liabilities:
Borrowings of consolidated VIEs			$2,402			($9	)		$-		$-			($343	)		$-		$-			$2,068		n/a	(4)
Other liabilities			-			-			-		-			33			-		-			33
Total Level 3 liabilities			$2,402			($9	)		$-		$-			($310	)		$-		$-			$2,101
	n/a	– not applicable
	(1)	Amounts primarily include distributions from equity method investees, repayments of borrowings of consolidated VIEs, elimination of investment related to a deconsolidation of a consolidated VIE, a reclassification of an investment from a consolidated sponsored investment fund to an equity method investment due to a change in ownership percentage and a contingent liability related to the acquisition of Credit Suisse’s ETF franchise.
	(2)	Earnings attributable to the change in unrealized gains (losses) relating to assets still held at the reporting date.
	(3)	The net investment income attributable to separate account assets accrues directly to the contract owners and is not reported on the condensed consolidated statements of income.
	(4)	The net gain (loss) on consolidated VIEs is solely attributable to noncontrolling interests on the condensed consolidated statements of income.
Changes in Level 3 Assets and Liabilities Measured at Fair Value on a Recurring Basis for the Three Months Ended September 30, 2012
(in millions)		June 30,			Realized			Purchases		Sales and			Issuances  and			Transfers		Transfers			September 30,		Total net gains
		2012			and					maturities			other			into		out of			2012		(losses)
					unrealized								settlements(1)			Level 3		Level 3					included in
					gains																		earnings(2)
					(losses) in
					earnings
					and OCI
Assets:
Investments
Available-for-sale:
Equity securities (CDOs)			$1			$-			$-		$-			$-			$-		$-			$1		$-
Consolidated sponsored investment funds:
Hedge funds / Funds of funds			46			8			3		(2	)		-			-		-			55		8
Private equity			298			22			-		(14	)		(8	)		-		-			298		20
Equity method:
Hedge funds / Funds of hedge funds			187			14			-		-			(21	)		-		-			180		14
Private equity investments			88			1			1		-			-			-		-			90		2
Real estate funds			101			6			6		(7	)		(3	)		-		-			103		4
Total Level 3 investments			721			51			10		(23	)		(32	)		-		-			727		48
Separate account assets			7			(4	)		6		(7	)		-			34		-			36		n/a	(3)
Assets of consolidated VIEs:
Bank loans			85			2			7		(24	)		7			36		(24	)		89
Bonds			44			1			-		-			-			-		-			45
Private equity			25			2			2		(3	)		-			-		-			26
Total Level 3 assets of consolidated VIEs			154			5			9		(27	)		7			36		(24	)		160		n/a	(4)
Total Level 3 assets			$882			$52			$25		($57	)		($25	)		$70		($24	)		$923
Liabilities:
Borrowings of consolidated VIEs			$1,439			($27	)		$-		$-			$377			$-		$-			$1,843		n/a	(4)
	n/a	– not applicable
	(1)	Amount primarily includes distributions from equity method investees, repayments of borrowings of consolidated VIEs, and loans and borrowings related to the consolidation of one additional CLO.
	(2)	Earnings attributable to the change in unrealized gains (losses) relating to assets still held at the reporting date.
	(3)	The net investment income attributable to separate account assets accrues directly to the contract owners and is not reported on the condensed consolidated statements of income.
	(4)	The net gain (loss) on consolidated VIEs is solely attributable to noncontrolling interests on the condensed consolidated statements of income.
Changes in Level 3 Assets and Liabilities Measured at Fair Value on a Recurring Basis for the Nine Months Ended September 30, 2012
(in millions)		December 31,			Realized			Purchases		Sales and			Issuances  and			Transfers		Transfers			September 30,		Total net gains
		2011			and					maturities			other			into		out of			2012		(losses)
					unrealized								settlements(1)			Level 3		Level 3					included in
					gains																		earnings(2)
					(losses) in
					earnings
					and OCI
Assets:
Investments
Available-for-sale:
Equity securities (CDOs)			$1			$-			$-		$-			$-			$-		$-			$1		$-
Consolidated sponsored investment funds:
Hedge funds / Funds of funds			22			4			30		(2	)		(2	)		3		-			55		4
Private equity			313			43			2		(46	)		(8	)		-		(6	)		298		38
Equity method:
Hedge funds / Funds of hedge funds			193			33			-		-			(46	)		-		-			180		33
Private equity investments			85			7			4		-			(6	)		-		-			90		8
Real estate funds			88			8			19		(7	)		(5	)		-		-			103		6
Total Level 3 investments			702			95			55		(55	)		(67	)		3		(6	)		727		89
Separate account assets			10			(5	)		10		(18	)		-			48		(9	)		36		n/a	(3)
Assets of consolidated VIEs:
Bank loans			83			2			25		(31	)		7			89		(86	)		89
Bonds			40			3			2		-			-			-		-			45
Private equity			27			4			2		(7	)		-			-		-			26
Total Level 3 assets of consolidated VIEs			150			9			29		(38	)		7			89		(86	)		160		n/a	(4)
Total Level 3 assets			$862			$99			$94		($111	)		($60	)		$140		($101	)		$923
Liabilities:
Borrowings of consolidated VIEs			$1,574			($66	)		$-		$-			$203			$-		$-			$1,843		n/a	(4)
	n/a	– not applicable
	(1)	Amount primarily includes distributions from equity method investees, repayments of borrowings of consolidated VIEs, and loans and borrowings related to the consolidation of one additional CLO.
	(2)	Earnings attributable to the change in unrealized gains (losses) relating to assets still held at the reporting date.
	(3)	The net investment income attributable to separate account assets accrues directly to the contract owners and is not reported on the condensed consolidated statements of income.
	(4)	The net gain (loss) on consolidated VIEs is solely attributable to noncontrolling interests on the condensed consolidated statements of income.
Fair Value of Financial Assets and Financial Liabilities	'
	At September 30, 2013 and December 31, 2012, the fair value of the Company’s financial instruments not held at fair value are categorized in the table below:
			September 30, 2013						December 31, 2012
	(in millions)		Carrying			Estimated			Carrying		Estimated			Fair Value
			Amount			Fair Value			Amount		Fair Value			Hierarchy
	Financial Assets:
	Cash and cash equivalents		$	3,987		$	3,987		$	4,606	$	4,606			Level 1	(1)
	Accounts receivable			4,311			4,311			2,250		2,250			Level 1	(2)
	Cash and cash equivalents of consolidated VIEs			93			93			297		297			Level 1	(1)
	Financial Liabilities:
	Accounts payable and accrued liabilities			3,322			3,322			1,055		1,055			Level 1	(2)
	Short-term borrowings			-			-			100		100			Level 1	(2)
	Long-term borrowings			4,938			5,310			5,687		6,275			Level 2	(3)
		(1)	Cash and cash equivalents are carried at either cost or amortized cost that approximates fair value due to their short-term maturities. At September 30, 2013 and December 31, 2012, approximately $76 million and $98 million, respectively, of money market funds were recorded within cash and cash equivalents on the condensed consolidated statements of financial condition. Money market funds are valued based on quoted market prices, or $1.00 per share, which generally is the NAV of the fund. At September 30, 2013 and December 31, 2012, approximately $105 million and $133 million, respectively, related to cash and cash equivalents held by consolidated sponsored investment funds.
		(2)	The carrying amounts of accounts receivable, accounts payable and accrued liabilities and short-term borrowings approximate fair value due to their short-term nature.
		(3)	Long-term borrowings are recorded at amortized cost. The fair value of the long-term borrowings, including the current portion of long-term borrowings, is estimated using market prices at the end of September 2013 and December 2012, respectively. See Note 11, Borrowings, for further information on the September 30, 2013 fair value of the Company’s long-term borrowings
Investments in Certain Entities Calculate Net Asset Value Per Share	'
	The following tables list information regarding all investments that use a fair value measurement to account for both their financial assets and financial liabilities in their calculation of a NAV per share (or equivalent).
	September 30, 2013
	(in millions)		Ref			Fair Value			Total Unfunded		Redemption		Redemption
									Commitments		Frequency		Notice Period
	Consolidated sponsored investment funds:
	Private equity funds of funds			(a	)		$202			$25	n/r		n/r
	Other funds of hedge funds			(b	)		57			-	Monthly (26%),		2 – 90 days
											Quarterly (2%),
											n/r (72%)
	Equity method:(1)
	Hedge funds/funds of hedge funds			(c	)		212			92	Monthly (2%), Quarterly (32%)		15 – 90 days
											n/r (66%)
	Private equity funds			(d	)		98			57	n/r		n/r
	Real estate funds			(e	)		123			11	Quarterly (16%)		60 days
											n/r (84%)
	Deferred compensation plan hedge fund investments			(f	)		11			-	Monthly (27%), Quarterly (73%)		60 – 90 days
	Consolidated VIEs:
	Private equity fund			(g	)		15			1	n/r		n/r
	Total						$718			$186
		n/r	– not redeemable
		(1)	Comprised of equity method investments, which include investment companies, which in accordance with GAAP account for their financial assets and most financial liabilities under fair value measures; therefore, the Company’s investment in such equity method investees approximates fair value.
	December 31, 2012
	(in millions)		Ref			Fair Value			Total		Redemption		Redemption
									Unfunded		Frequency		Notice Period
									Commitments
	Consolidated sponsored investment funds:
	Private equity funds of funds			(a	)		$212			$32	n/r		n/r
	Other funds of hedge funds			(b	)		98			-	Monthly (22%)		1 – 90 days
											Quarterly (11%)
											n/r (67%)
	Equity method:(1)
	Hedge funds/funds of hedge funds			(c	)		222			42	Monthly (2%)		15 – 90 days
											Quarterly (28%)
											n/r (70%)
	Private equity funds			(d	)		90			135	n/r		n/r
	Real estate funds			(e	)		107			15	Quarterly (18%)		60 days
											n/r (82%)
	Deferred compensation plan hedge fund investments			(f	)		9			-	Monthly (33%)		60 – 90 days
											Quarterly (67%)
	Consolidated VIE:
	Private equity funds			(g	)		20			1	n/r		n/r
	Trading:
	Equity			(h	)		3			-	Daily (100%)		None
	Total						$761			$225
		n/r	– not redeemable
		(1)	Comprised of equity method investments, which include investment companies, which in accordance with GAAP account for their financial assets and most financial liabilities under fair value measures; therefore, the Company’s investment in such equity method investees approximates fair value.
		(a)	This category includes the underlying third-party private equity funds within consolidated BlackRock sponsored private equity funds of funds. The fair values of the investments in the third-party funds have been estimated using capital accounts representing the Company’s ownership interest in each fund in the portfolio as well as other performance inputs. These investments are not subject to redemption; however, for certain funds, the Company may sell or transfer its interest, which may need approval by the general partner of the underlying funds. Due to the nature of the investments in this category, the Company reduces its investment by distributions that are received through the realization of the underlying assets of the funds. It is estimated that the underlying assets of these funds will be liquidated over a weighted-average period of approximately seven years at both September 30, 2013 and December 31, 2012. The total remaining unfunded commitments to other third-party funds were $25 million and $32 million at September 30, 2013 and December 31, 2012, respectively. The Company was contractually obligated to fund $30 million at both September 30, 2013 and December 31, 2012 to the consolidated funds.
		(b)	This category includes consolidated funds of hedge funds that invest in multiple strategies to diversify risks. The fair values of the investments have been estimated using the NAV of the fund’s ownership interest in partners’ capital of each fund in the portfolio. Certain of the underlying funds can be redeemed as long as there are no restrictions in place. At September 30, 2013 and December 31, 2012, the underlying funds that are currently restricted from redemptions within one year will be redeemable in approximately 12 to 24 months. This category also includes a consolidated offshore feeder fund that invests in a master fund with multiple alternative investment strategies. The fair value of this investment has been estimated using the NAV of the master offshore fund held by the feeder fund. The investment is currently subject to restrictions in place by the underlying master fund.
		(c)	This category includes hedge funds and funds of hedge funds that invest primarily in equities, fixed income securities, distressed credit and mortgage instruments and other third-party hedge funds. The fair values of the investments have been estimated using the NAV of the Company’s ownership interest in partners’ capital. It was estimated that the investments in the funds that are not subject to redemption will be liquidated over a weighted-average period of approximately four and five years at September 30, 2013 and December 31, 2012, respectively.
		(d)	This category includes several private equity funds that initially invest in nonmarketable securities of private companies, which ultimately may become public in the future. The fair values of these investments have been estimated using capital accounts representing the Company’s ownership interest in the funds as well as other performance inputs. The Company’s investment in each fund is not subject to redemption and is normally returned through distributions as a result of the liquidation of the underlying assets of the private equity funds. It was estimated that the investments in these funds will be liquidated over a weighted-average period of approximately five years at both September 30, 2013 and December 31, 2012.
		(e)	This category includes several real estate funds that invest directly in real estate and real estate related assets. The fair values of the investments have been estimated using capital accounts representing the Company’s ownership interest in the funds. A majority of the Company’s investments are not subject to redemption or are not currently redeemable and is normally returned through distributions as a result of the liquidation of the underlying assets of the real estate funds. It is estimated that the investments in these funds not subject to redemptions will be liquidated over a weighted-average period of approximately seven years at September 30, 2013 and eight years at December 31, 2012.
		(f)	This category includes investments in certain hedge funds that invest in energy and health science related equity securities. The fair values of the investments in this category have been estimated using capital accounts representing the Company’s ownership interest in partners’ capital as well as performance inputs. The investments in these funds will be redeemed upon settlement of certain deferred compensation liabilities.
		(g)	This category includes the underlying third-party private equity funds within one consolidated BlackRock sponsored private equity fund of funds. The fair values of the investments in the third-party funds have been estimated using capital accounts representing the Company’s ownership interest in each fund in the portfolio as well as other performance inputs. These investments are not subject to redemption; however, for certain funds the Company may sell or transfer its interest, which may need approval by the general partner of the underlying third-party funds. Due to the nature of the investments in this category, the Company reduces its investment by distributions that are received through the realization of the underlying assets of the funds. It is estimated that the underlying assets of these funds will be liquidated over a weighted-average period of approximately two years at September 30, 2013 and three years at December 31, 2012. Total remaining unfunded commitments to other third-party funds were $1 million at both September 30, 2013 and December 31, 2012, which commitments are required to be funded by capital contributions from noncontrolling interest holders.
		(h)	This category includes consolidated offshore feeder funds that invest in master funds with multiple equity strategies to diversify risks. The fair values of the investments in this category have been estimated using the NAV of master offshore funds held by the feeder funds. Investments in this category generally can be redeemed at any time, as long as there are no restrictions in place by the underlying master funds.
Summary of Information Related to Those Assets and Liabilities Selected for Fair Value Accounting	'
	The following table summarizes information related to those assets and liabilities selected for fair value accounting at September 30, 2013 and December 31, 2012:
	(in millions)		September 30,			December 31,
			2013			2012
	CLO Bank Loans:
	Aggregate principal amounts outstanding			$1,976			$2,124
	Fair value			1,964			2,110
	Aggregate unpaid principal balance in excess of (less than) fair value			$12			$14
	Unpaid principal balance of loans more than 90 days past due			$12			$4
	Aggregate fair value of loans more than 90 days past due			7			-
	Aggregate unpaid principal balance in excess of fair value for loans more than 90 days past due			$5			$4
	CLO Borrowings:
	Aggregate principal amounts outstanding			$2,201			$2,535
	Fair value			$2,068			$2,402

Variable_Interest_Entities_Tab

Variable Interest Entities (Tables)	9 Months Ended
	Sep. 30, 2013
Text Block [Abstract]	'
Balances Relating to Variable Interest Entities in which BlackRock is Primary Beneficiary	'
	At September 30, 2013 and December 31, 2012, the following balances related to VIEs were consolidated on the condensed consolidated statements of financial condition:
	(in millions)		September 30, 2013		December 31, 2012
	Assets of consolidated VIEs:
	Cash and cash equivalents			$93		$297
	Bank loans			1,964		2,110
	Bonds			99		124
	Other investments and other assets			44		30
	Total bank loans, bonds, other investments and other assets			2,107		2,264
	Liabilities of consolidated VIEs:
	Borrowings			-2,068		-2,402
	Other liabilities			-88		-103
	Appropriated retained earnings			-25		-29
	Noncontrolling interests of consolidated VIEs			-19		-27
	Total BlackRock net interests in consolidated VIEs			$-		$-
Balances Relating to Variable Interest Entities in which BlackRock is Not Primary Beneficiary	'
	At September 30, 2013 and December 31, 2012, the Company’s carrying value of assets and liabilities and its maximum risk of loss related to VIEs for which it was the sponsor or in which it held a variable interest, but for which it was not the PB, was as follows:
	(in millions)		Variable Interests on the Condensed
			Consolidated
			Statement of Financial Condition
	At September 30, 2013		Investments		Advisory		Other Net		Maximum
					Fee		Assets		Risk of Loss (1)
					Receivables		(Liabilities)
	CDOs/CLOs			$1		$1		($4)		$19
	Other sponsored investment funds:
	Collective trusts			-		166		-		166
	Other			18		130		-5		148
	Total			$19		$297		($9)		$333
	At December 31, 2012
	CDOs/CLOs			$1		$1		($5)		$19
	Other sponsored investment funds:
	Collective trusts			-		248		-		248
	Other			17		61		-3		77
	Total			$18		$310		($8)		$344
	(1)	At both September 30, 2013 and December 31, 2012, BlackRock’s maximum risk of loss associated with these VIEs primarily related to: (i) advisory fee receivables; (ii) BlackRock’s investments; and (iii) $17 million of credit protection sold by BlackRock to a third party in a synthetic CDO transaction.
Unconsolidated Collateralized Debt or Loan Obligations and Other Sponsored Investment Funds	'
	The net assets related to the above CDOs/CLOs and other sponsored investment funds, including collective trusts, that the Company does not consolidate were as follows:
	CDOs/CLOs
	(in billions)		September 30, 2013		December 31, 2012
	Assets at fair value			$3		$4
	Liabilities(1)			5		5
	Net assets			($2)		($1)
	(1)	Amounts primarily comprised of unpaid principal debt obligations to CDO/CLO debt holders.

Goodwill_Tables

Goodwill (Tables)	9 Months Ended
	Sep. 30, 2013
Goodwill And Intangible Assets Disclosure [Abstract]	'
Goodwill Activity	'
	Goodwill activity during the nine months ended September 30, 2013 was as follows:
	(in millions)
	December 31, 2012		$12,910
	Acquisition (1)		44
	Goodwill adjustment related to Quellos and other (2)		(16	)
	September 30, 2013		$12,938
	-1	Amount represents goodwill from the Company’s acquisition of Credit Suisse’s ETF franchise on July 1, 2013 for approximately $273 million (the “Credit Suisse ETF Transaction”).
	(2)	The decrease in goodwill during the nine months ended September 30, 2013 primarily resulted from a decline related to tax benefits realized from tax-deductible goodwill in excess of book goodwill from the acquisition of the fund-of-funds business of Quellos Group, LLC in October 2007 (the “Quellos Transaction”). Goodwill related to the Quellos Transaction will continue to be reduced in future periods by the amount of tax benefits realized from tax-deductible goodwill in excess of book goodwill from the Quellos Transaction. The balance of the Quellos tax-deductible goodwill in excess of book goodwill was approximately $301 million and $324 million at September 30, 2013 and December 31, 2012, respectively.

Intangible_Assets_Tables

Intangible Assets (Tables)	9 Months Ended
	Sep. 30, 2013
Goodwill And Intangible Assets Disclosure [Abstract]	'
Carrying Amounts of Identifiable Intangible Assets	'
	The carrying amounts of identifiable intangible assets are summarized as follows:
	(in millions)		Indefinite-lived		Finite-lived			Total
			intangible assets		intangible assets			intangible assets
	December 31, 2012			$16,760		$642			$17,402
	Acquisition(1)			231		-			231
	Amortization expense			-		(120	)		(120	)
	September 30, 2013			$16,991		$522			$17,513
	-1	Amount represents indefinite-lived management contracts acquired in the Credit Suisse ETF Transaction.

Borrowings_Tables

Borrowings (Tables)	9 Months Ended
	Sep. 30, 2013
Debt Disclosure [Abstract]	'
Carrying Value and Fair Value of Long-Term Borrowings	'
	The carrying value and fair value of long-term borrowings determined using market prices at the end of September 2013 included the following:
	(in millions)	Maturity Amount		Unamortized		Carrying Value		Fair Value
				Discount
	3.50% Notes due 2014		$1,000		$-		$1,000		$1,036
	1.375% Notes due 2015		750		-		750		762
	6.25% Notes due 2017		700		-2		698		818
	5.00% Notes due 2019		1,000		-2		998		1,147
	4.25% Notes due 2021		750		-4		746		798
	3.375% Notes due 2022		750		-4		746		749
	Total Long-term Borrowings		$4,950		($12)		$4,938		$5,310

StockBased_Compensation_Tables

Stock-Based Compensation (Tables)	9 Months Ended
	Sep. 30, 2013
Restricted Stock and Restricted Stock Units ("RSUs") Activity	'
	Restricted stock and restricted stock units (“RSUs”) activity for the nine months ended September 30, 2013 is summarized below:
	Outstanding at		Restricted			Weighted-
			Stock and			Average
			RSUs			Grant Date
						Fair Value
	31-Dec-12			5,620,835			$197.90
	Granted			1,645,277			$234.69
	Converted			-2,502,869			$204.46
	Forfeited			-70,491			$204.41
	September 30, 2013(1)			4,692,752			$207.20
	(1)	At September 30, 2013, approximately 4.4 million awards are expected to vest and 0.3 million awards have vested but have not been converted.
Stock Option Activity	'
	Stock Options. Stock option activity for the nine months ended September 30, 2013 is summarized below:
	Outstanding at		Shares Under			Weighted-
			Option			Average
						Exercise
						Price
	December 31, 2012			1,099,909		$	167.76
	Exercised			(85,090	)	$	167.76
	September 30, 2013			1,014,819		$	167.76
Market Performance-based RSUs [Member]	'
Restricted Stock and Restricted Stock Units ("RSUs") Activity	'
	Market performance-based RSU activity for the nine months ended September 30, 2013 is summarized below:
	Outstanding at		Market			Weighted-
			Performance-			Average
			Based RSUs			Grant Date
						Fair Value
	December 31, 2012			575,532		$	115.03
	Granted			556,581		$	126.76
	September 30, 2013 (1)			1,132,113		$	120.8
	(1)	At September 30, 2013, approximately 1.1 million awards are expected to vest and no awards have vested and have been converted.

Accumulated_Other_Comprehensiv1

Accumulated Other Comprehensive Income (Loss) (Tables)	9 Months Ended
	Sep. 30, 2013
Text Block [Abstract]	'
Changes in Accumulated Other Comprehensive Income	'
	The following table presents changes in AOCI by component for the three and nine months ended September 30, 2013:
	(in millions)		Unrealized gains			Benefit plans			Foreign			Total (1)
			(losses) on						currency
			available-for-sale						translation
			investments						adjustments
	June 30, 2013			$8			($4	)		($202	)		($198	)
	Other comprehensive income (loss) before reclassifications(2)			2			-			118			120
	Amount reclassified from AOCI(3)			(1	)		-			-			(1	)
	Net other comprehensive income (loss) for the three months ended September 30, 2013			1			-			118			119
	September 30, 2013			$9			($4	)		($84	)		($79	)
	(in millions)		Unrealized gains			Benefit plans			Foreign			Total (1)
			(losses) on						currency
			available-for-sale						translation
			investments						adjustments
	December 31, 2012			$16			($4	)		($71	)		($59	)
	Other comprehensive income (loss) before reclassifications(2)			3			-			(13	)		(10	)
	Amount reclassified from AOCI(3)			(10	)		-			-			(10	)
	Net other comprehensive income (loss) for the nine months ended September 30, 2013			(7	)		-			(13	)		(20	)
	September 30, 2013			$9			($4	)		($84	)		($79	)
	(1)	All amounts are net of tax.
	(2)	The tax benefit (expense) was not material for the three and nine months ended September 30, 2013.
	(3)	The tax benefit (expense) was not material for the three and nine months ended September 30, 2013. The pre-tax amount reclassified from AOCI was included in net gain (loss) on investments on the condensed consolidated statements of income.

Capital_Stock_Tables

Capital Stock (Tables)	9 Months Ended
	Sep. 30, 2013
Equity [Abstract]	'
Preferred Shares Authorized, Issued and Outstanding	'
	Nonvoting Participating Preferred Stock.    The Company’s preferred shares authorized, issued and outstanding consisted of the following:
		September 30,		December 31,
		2013		2012
	Series A
	Shares authorized, $0.01 par value		20,000,000		20,000,000
	Shares issued and outstanding		-		-
	Series B
	Shares authorized, $0.01 par value		150,000,000		150,000,000
	Shares issued and outstanding		823,188		823,188
	Series C
	Shares authorized, $0.01 par value		6,000,000		6,000,000
	Shares issued and outstanding		1,311,887		1,517,237
	Series D
	Shares authorized, $0.01 par value		20,000,000		20,000,000
	Shares issued and outstanding		-		-

Earnings_Per_Share_Tables

Earnings Per Share (Tables)	9 Months Ended
	Sep. 30, 2013
Earnings Per Share [Abstract]	'
Computation of Basic and Diluted EPS under Treasury Stock Method and Two-Class Method	'
	The following table sets forth the computation of basic and diluted EPS for the three and nine months ended September 30, 2013 under the treasury stock method:
	( in millions, except share data)		Three Months		Nine Months
			Ended		Ended
			September 30,		September 30,
			2013		2013
	Net income attributable to BlackRock			$730		$2,091
	Basic weighted-average shares outstanding			169,811,633		170,581,930
	Dilutive effect of nonparticipating RSUs and stock options			3,559,875		3,430,946
	Total diluted weighted-average shares outstanding			173,371,508		174,012,876
	Basic earnings per share			$4.30		$12.26
	Diluted earnings per share			$4.21		$12.02
	The following table sets forth the computation of basic and diluted EPS for the three and nine months ended September 30, 2012 under the two-class method:
	(in millions, except share data)		Three Months		Nine Months
			Ended		Ended
			September 30,		September 30,
			2012		2012
	Net income attributable to BlackRock			$642		$1,768
	Less:
	Dividends distributed to common shares			259		803
	Dividends distributed to participating RSUs			-		1
	Undistributed net income attributable to BlackRock			383		964
	Percentage of undistributed net income allocated to common shares(1)			99.90%		99.90%
	Undistributed net income allocated to common shares			382		963
	Plus:
	Common share dividends			259		803
	Net income attributable to common shares			$641		$1,766
	Basic weighted-average shares outstanding			172,359,141		176,116,975
	Dilutive effect of nonparticipating RSUs and stock options			3,091,391		2,839,724
	Total diluted weighted-average shares outstanding			175,450,532		178,956,699
	Basic earnings per share			$3.72		$10.02
	Diluted earnings per share			$3.65		$9.87
		(1)	Allocation to common stockholders was based on the total of common shares and participating securities (which represent unvested RSUs that contain nonforfeitable rights to dividends). For the three months and nine months ended September 30, 2012, average outstanding participating securities were 0.2 million.

Segment_Information_Tables

Segment Information (Tables)	9 Months Ended
	Sep. 30, 2013
Segment Reporting [Abstract]	'
Schedule of Investment Advisory, Administration Fees, Securities Lending Revenue and Performance Fees, BlackRock Solutions and Advisory Revenue, Distribution Fees and Other Revenue	'
	The following table illustrates investment advisory, administration fees, securities lending revenue and performance fees, BlackRock Solutions® and advisory revenue, distribution fees and other revenue for the three and nine months ended September 30, 2013 and 2012, respectively.
		Three Months Ended						Nine Months Ended
		September 30,						September 30,
	(in millions)	2013				2012		2013		2012
	Equity	$	1,170			$	1,073	$	3,525	$	3,196
	Fixed income		490				491		1,488		1,386
	Multi-asset		266				241		777		724
	Alternatives		248				232		718		642
	Cash management		75				90		244		267
	Total investment advisory, administration fees, securities lending revenue and performance fees		2,249				2,127		6,752		6,215
	BlackRock Solutions and advisory		156				128		420		382
	Distribution fees		19				19		54		58
	Other revenue		48				46		177		143
	Total revenue	$	2,472			$	2,320	$	7,403	$	6,798
Total Revenue by Geographic Region	'
	The following table illustrates total revenue for the three and nine months ended September 30, 2013 and 2012, respectively, by geographic region. These amounts are aggregated on a legal entity basis and do not necessarily reflect where the customer resides.
	(in millions)	Three Months Ended						Nine Months Ended
		September 30,						September 30,
	Revenue	2013				2012		2013		2012
	Americas	$	1,632			$	1,578	$	4,967	$	4,676
	Europe		726				629		2,060		1,795
	Asia-Pacific		114				113		376		327
	Total revenue	$	2,472			$	2,320	$	7,403	$	6,798
Schedule of Long-Lived Assets by Geographic Region	'
	The following table illustrates long-lived assets that consist of goodwill and property and equipment at September 30, 2013 and December 31, 2012 by geographic region. These amounts are aggregated on a legal entity basis and do not necessarily reflect where the asset is physically located.
	(in millions)			September 30,				December 31,
	Long-lived Assets			2013				2012
	Americas			$	13,197			$	13,238
	Europe				207				166
	Asia-Pacific				57				63
	Total long-lived assets			$	13,461			$	13,467

Business_Overview_Additional_I

Business Overview - Additional Information (Detail)	Sep. 30, 2013
Voting common stock [Member]	'
Schedule of Equity Method Investments [Line Items]	'
Equity ownership percentage	20.90%
Nonvoting Common Stock [Member]	'
Schedule of Equity Method Investments [Line Items]	'
Equity ownership percentage	21.90%

Significant_Accounting_Policie2

Significant Accounting Policies - Additional Information (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
New Accounting Pronouncements or Change in Accounting Principle [Line Items]	'	'
Fair value of loaned securities	$20,200,000,000	$21,000,000,000
Fair value of collateral held for loan securities	$21,962,000,000	$23,021,000,000
Minimum [Member]	'	'
New Accounting Pronouncements or Change in Accounting Principle [Line Items]	'	'
Collateral cash and securities received in exchange of value of securities lent in order to reduce counterparty risk	102.00%	'
Maximum [Member]	'	'
New Accounting Pronouncements or Change in Accounting Principle [Line Items]	'	'
Collateral cash and securities received in exchange of value of securities lent in order to reduce counterparty risk	112.00%	'

Investments_Summary_of_Carryin

Investments - Summary of Carrying Value of Investments (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Investment [Line Items]	'	'
Available-for-sale investments	$168	$158
Held-to-maturity investments	57	112
Total trading investments	505	270
Consolidated sponsored investment funds	314	401
Equity method investments	564	595
Cost method investments	122	120
Carried interest	137	85
Total other investments	1,148	1,210
Total investments	1,878	1,750
Consolidated sponsored investment funds [Member]	'	'
Investment [Line Items]	'	'
Total trading investments	381	123
Total other investments	314	401
Total investments	695	524
Other equity and debt securities [Member]	'	'
Investment [Line Items]	'	'
Total trading investments	67	94
Deferred compensation plan fund [Member]	'	'
Investment [Line Items]	'	'
Total trading investments	57	53
Equity method investments	11	9
Total other investments	$11	$9

Investments_Additional_Informa

Investments - Additional Information (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Investment [Line Items]	'	'
Total investments	$1,878	$1,750
Total trading investments	505	270
Other investments	1,148	1,210
Foreign government debt	57	112
Foreign government debt, one year or less	43	'
Foreign government debt, after ten years	14	'
Consolidated sponsored investment funds [Member]	'	'
Investment [Line Items]	'	'
Total investments	695	524
Total trading investments	381	123
Other investments	314	401
Trading securities, equity	187	'
Trading securities, debt	194	'
Deferred compensation plan fund [Member]	'	'
Investment [Line Items]	'	'
Total trading investments	57	53
Other investments	11	9
Equity And Debt Securities Held In Separate Investment Accounts [Member]	'	'
Investment [Line Items]	'	'
Total trading investments	$67	'

Investments_Summary_of_Cost_an

Investments - Summary of Cost and Carrying Value of Investments Classified as Available-for-Sale (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Schedule of Investments [Line Items]	'	'
Available-for-sale investments, Cost	$164	$144
Available-for-sale investments, Gross Unrealized Gains	8	15
Available-for-sale investments, Gross Unrealized Losses	-4	-1
Available-for-sale investments, Carrying Value	168	158
Equity securities of sponsored investment funds [Member]	'	'
Schedule of Investments [Line Items]	'	'
Available-for-sale investments, Cost	163	142
Available-for-sale investments, Gross Unrealized Gains	6	14
Available-for-sale investments, Gross Unrealized Losses	-4	-1
Available-for-sale investments, Carrying Value	165	155
Other securities [Member]	'	'
Schedule of Investments [Line Items]	'	'
Available-for-sale investments, Cost	1	2
Available-for-sale investments, Gross Unrealized Gains	2	1
Available-for-sale investments, Gross Unrealized Losses	'	'
Available-for-sale investments, Carrying Value	$3	$3

Investments_Summary_of_Cost_an1

Investments - Summary of Cost and Carrying Value of Trading Investments (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Schedule of Investments [Line Items]	'	'
Cost	$499	$255
Carrying Value	505	270
Deferred compensation plan fund [Member]	'	'
Schedule of Investments [Line Items]	'	'
Cost	51	46
Carrying Value	57	53
Equity/Multi-asset mutual funds [Member]	'	'
Schedule of Investments [Line Items]	'	'
Cost	190	154
Carrying Value	194	162
Corporate debt [Member]	'	'
Schedule of Investments [Line Items]	'	'
Cost	126	44
Carrying Value	126	44
Government debt [Member]	'	'
Schedule of Investments [Line Items]	'	'
Cost	132	11
Carrying Value	$128	$11

Investments_Summary_of_Cost_an2

Investments - Summary of Cost and Carrying Value of Other Investments (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Schedule of Investments [Line Items]	'	'
Cost	$902	$1,054
Carrying Value	1,148	1,210
Consolidated sponsored investment funds [Member]	'	'
Schedule of Investments [Line Items]	'	'
Cost	303	378
Carrying Value	314	401
Equity method [Member]	'	'
Schedule of Investments [Line Items]	'	'
Cost	480	541
Carrying Value	564	595
Deferred compensation plan fund [Member]	'	'
Schedule of Investments [Line Items]	'	'
Cost	9	15
Carrying Value	11	9
Federal reserve bank stock [Member]	'	'
Schedule of Investments [Line Items]	'	'
Cost	93	89
Carrying Value	93	89
Other [Member]	'	'
Schedule of Investments [Line Items]	'	'
Cost	17	31
Carrying Value	29	31
Total cost method investments [Member]	'	'
Schedule of Investments [Line Items]	'	'
Cost	110	120
Carrying Value	122	120
Carried interest [Member]	'	'
Schedule of Investments [Line Items]	'	'
Cost	'	'
Carrying Value	$137	$85

Consolidated_Sponsored_Investm2

Consolidated Sponsored Investment Funds - Consolidated Sponsored Investment Funds Included in Condensed Consolidated Statements of Financial Condition (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2012	Dec. 31, 2011
In Millions, unless otherwise specified
Consolidated Sponsored Investment Funds [Line Items]	'	'	'	'
Cash and cash equivalents	$3,987	$4,606	$4,223	$3,506
Trading investments	505	270	'	'
Other investments	1,148	1,210	'	'
Other assets	759	626	'	'
Other liabilities	-948	-858	'	'
Noncontrolling interests	-127	-155	'	'
Consolidated sponsored investment funds [Member]	'	'	'	'
Consolidated Sponsored Investment Funds [Line Items]	'	'	'	'
Cash and cash equivalents	105	133	'	'
Trading investments	381	123	'	'
Other investments	314	401	'	'
Other assets	13	25	'	'
Other liabilities	-33	-65	'	'
Noncontrolling interests	-168	-187	'	'
BlackRock's net interests in consolidated sponsored investment funds	$612	$430	'	'

Consolidated_Sponsored_Investm3

Consolidated Sponsored Investment Funds - Additional Information (Detail) (Consolidated sponsored investment funds [Member], USD $)	Sep. 30, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Consolidated sponsored investment funds [Member]	'	'
Schedule of Investments [Line Items]	'	'
BlackRock's total exposure to consolidated sponsored investment funds	$612	$430

Fair_Value_Disclosures_Assets_

Fair Value Disclosures - Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total available-for-sale	$168	$158
Total trading	505	270
Separate account assets	146,646	134,768
Total separate account collateral held under securities lending agreements	21,962	23,021
Separate account collateral liabilities under securities lending agreements	21,962	23,021
Significant Unobservable Inputs (Level 3) [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total investments	626	679
Fair Value, Measurements, Recurring [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total available-for-sale	168	158
Total trading	505	270
Total consolidated sponsored investment funds	314	401
Total equity method	564	595
Deferred compensation plan hedge fund equity method investments	11	9
Cost method investments	122	120
Carried interest	137	85
Total investments	1,878	1,750
Separate account assets	146,646	134,768
Total separate account collateral held under securities lending agreements	21,962	23,021
Other assets	12	12
Total	172,605	161,815
Separate account collateral liabilities under securities lending agreements	21,962	23,021
Other liabilities	56	20
Total liabilities measured at fair value	24,086	25,443
Fair Value, Measurements, Recurring [Member] | Variable Interest Entity, Primary Beneficiary, Aggregated Disclosure [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total assets of consolidated VIEs	2,107	2,264
Borrowings of consolidated VIEs	2,068	2,402
Fair Value, Measurements, Recurring [Member] | Equity Securities [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total available-for-sale	166	156
Total separate account collateral held under securities lending agreements	19,851	21,273
Fair Value, Measurements, Recurring [Member] | Debt Securities [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total available-for-sale	2	2
Held-to-maturity debt securities	57	112
Total separate account collateral held under securities lending agreements	2,111	1,748
Fair Value, Measurements, Recurring [Member] | Deferred Compensation Plan Mutual Funds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total trading	57	53
Fair Value, Measurements, Recurring [Member] | Equity/Multi-asset Mutual Funds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total trading	194	162
Fair Value, Measurements, Recurring [Member] | Debt Securities/ Fixed Income Mutual Fund [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total trading	254	55
Fair Value, Measurements, Recurring [Member] | Hedge Funds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total consolidated sponsored investment funds	67	115
Fair Value, Measurements, Recurring [Member] | Private/ Public Equity [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total consolidated sponsored investment funds	247	286
Fair Value, Measurements, Recurring [Member] | Private/ Public Equity [Member] | Variable Interest Entity, Primary Beneficiary, Aggregated Disclosure [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total assets of consolidated VIEs	44	30
Fair Value, Measurements, Recurring [Member] | Equity Method, Hedge Funds/Funds of Hedge Funds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total equity method	267	261
Fair Value, Measurements, Recurring [Member] | Equity Method, Private Equity Funds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total equity method	98	90
Fair Value, Measurements, Recurring [Member] | Equity Method, Real Estate Funds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total equity method	130	122
Fair Value, Measurements, Recurring [Member] | Fixed Income Mutual Securities [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total equity method	63	46
Fair Value, Measurements, Recurring [Member] | Equity Multi Asset Class Alternative Mutual Funds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total equity method	6	76
Fair Value, Measurements, Recurring [Member] | Bank Loans and Other Assets [Member] | Variable Interest Entity, Primary Beneficiary, Aggregated Disclosure [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total assets of consolidated VIEs	1,984	2,110
Fair Value, Measurements, Recurring [Member] | Bonds [Member] | Variable Interest Entity, Primary Beneficiary, Aggregated Disclosure [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total assets of consolidated VIEs	99	124
Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total available-for-sale	165	155
Total trading	312	217
Total consolidated sponsored investment funds	6	13
Total equity method	69	122
Deferred compensation plan hedge fund equity method investments	'	'
Cost method investments	'	'
Carried interest	'	'
Total investments	552	507
Separate account assets	106,085	95,514
Total separate account collateral held under securities lending agreements	19,851	21,273
Other assets	'	'
Total	126,488	117,296
Separate account collateral liabilities under securities lending agreements	19,851	21,273
Other liabilities	19	15
Total liabilities measured at fair value	19,870	21,288
Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Variable Interest Entity, Primary Beneficiary, Aggregated Disclosure [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total assets of consolidated VIEs	'	2
Borrowings of consolidated VIEs	'	'
Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Equity Securities [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total available-for-sale	165	155
Total separate account collateral held under securities lending agreements	19,851	21,273
Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Debt Securities [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total available-for-sale	'	'
Held-to-maturity debt securities	'	'
Total separate account collateral held under securities lending agreements	'	'
Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Deferred Compensation Plan Mutual Funds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total trading	57	53
Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Equity/Multi-asset Mutual Funds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total trading	194	159
Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Debt Securities/ Fixed Income Mutual Fund [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total trading	61	5
Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Hedge Funds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total consolidated sponsored investment funds	1	3
Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Private/ Public Equity [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total consolidated sponsored investment funds	5	10
Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Private/ Public Equity [Member] | Variable Interest Entity, Primary Beneficiary, Aggregated Disclosure [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total assets of consolidated VIEs	'	2
Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Equity Method, Hedge Funds/Funds of Hedge Funds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total equity method	'	'
Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Equity Method, Private Equity Funds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total equity method	'	'
Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Equity Method, Real Estate Funds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total equity method	'	'
Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Fixed Income Mutual Securities [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total equity method	63	46
Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Equity Multi Asset Class Alternative Mutual Funds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total equity method	6	76
Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Bank Loans and Other Assets [Member] | Variable Interest Entity, Primary Beneficiary, Aggregated Disclosure [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total assets of consolidated VIEs	'	'
Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Bonds [Member] | Variable Interest Entity, Primary Beneficiary, Aggregated Disclosure [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total assets of consolidated VIEs	'	'
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total available-for-sale	2	2
Total trading	193	53
Total consolidated sponsored investment funds	29	49
Total equity method	87	80
Deferred compensation plan hedge fund equity method investments	11	9
Cost method investments	'	'
Carried interest	'	'
Total investments	322	193
Separate account assets	39,675	38,392
Total separate account collateral held under securities lending agreements	2,111	1,748
Other assets	12	12
Total	44,058	42,433
Separate account collateral liabilities under securities lending agreements	2,111	1,748
Other liabilities	4	5
Total liabilities measured at fair value	2,115	1,753
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Variable Interest Entity, Primary Beneficiary, Aggregated Disclosure [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total assets of consolidated VIEs	1,938	2,088
Borrowings of consolidated VIEs	'	'
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Equity Securities [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total available-for-sale	'	'
Total separate account collateral held under securities lending agreements	'	'
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Debt Securities [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total available-for-sale	2	2
Held-to-maturity debt securities	'	'
Total separate account collateral held under securities lending agreements	2,111	1,748
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Deferred Compensation Plan Mutual Funds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total trading	'	'
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Equity/Multi-asset Mutual Funds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total trading	'	3
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Debt Securities/ Fixed Income Mutual Fund [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total trading	193	50
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Hedge Funds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total consolidated sponsored investment funds	21	39
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Private/ Public Equity [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total consolidated sponsored investment funds	8	10
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Private/ Public Equity [Member] | Variable Interest Entity, Primary Beneficiary, Aggregated Disclosure [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total assets of consolidated VIEs	7	6
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Equity Method, Hedge Funds/Funds of Hedge Funds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total equity method	67	61
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Equity Method, Private Equity Funds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total equity method	'	'
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Equity Method, Real Estate Funds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total equity method	20	19
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Fixed Income Mutual Securities [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total equity method	'	'
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Equity Multi Asset Class Alternative Mutual Funds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total equity method	'	'
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Bank Loans and Other Assets [Member] | Variable Interest Entity, Primary Beneficiary, Aggregated Disclosure [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total assets of consolidated VIEs	1,867	2,004
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Bonds [Member] | Variable Interest Entity, Primary Beneficiary, Aggregated Disclosure [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total assets of consolidated VIEs	64	78
Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total available-for-sale	1	1
Total trading	'	'
Total consolidated sponsored investment funds	279	339
Total equity method	346	339
Deferred compensation plan hedge fund equity method investments	'	'
Cost method investments	'	'
Carried interest	'	'
Total investments	626	679
Separate account assets	'	2
Total separate account collateral held under securities lending agreements	'	'
Other assets	'	'
Total	775	855
Separate account collateral liabilities under securities lending agreements	'	'
Other liabilities	33	'
Total liabilities measured at fair value	2,011	2,402
Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Variable Interest Entity, Primary Beneficiary, Aggregated Disclosure [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total assets of consolidated VIEs	149	174
Borrowings of consolidated VIEs	2,068	2,402
Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Equity Securities [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total available-for-sale	1	1
Total separate account collateral held under securities lending agreements	'	'
Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Debt Securities [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total available-for-sale	'	'
Held-to-maturity debt securities	'	'
Total separate account collateral held under securities lending agreements	'	'
Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Deferred Compensation Plan Mutual Funds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total trading	'	'
Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Equity/Multi-asset Mutual Funds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total trading	'	'
Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Debt Securities/ Fixed Income Mutual Fund [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total trading	'	'
Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Hedge Funds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total consolidated sponsored investment funds	45	73
Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Private/ Public Equity [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total consolidated sponsored investment funds	234	266
Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Private/ Public Equity [Member] | Variable Interest Entity, Primary Beneficiary, Aggregated Disclosure [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total assets of consolidated VIEs	17	22
Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Equity Method, Hedge Funds/Funds of Hedge Funds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total equity method	145	161
Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Equity Method, Private Equity Funds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total equity method	98	90
Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Equity Method, Real Estate Funds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total equity method	103	88
Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Fixed Income Mutual Securities [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total equity method	'	'
Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Equity Multi Asset Class Alternative Mutual Funds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total equity method	'	'
Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Bank Loans and Other Assets [Member] | Variable Interest Entity, Primary Beneficiary, Aggregated Disclosure [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total assets of consolidated VIEs	97	106
Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Bonds [Member] | Variable Interest Entity, Primary Beneficiary, Aggregated Disclosure [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total assets of consolidated VIEs	35	46
Fair Value, Measurements, Recurring [Member] | Other Assets Not Held at Fair Value [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total available-for-sale	'	'
Total trading	'	'
Total consolidated sponsored investment funds	'	'
Total equity method	62	54
Deferred compensation plan hedge fund equity method investments	'	'
Cost method investments	122	120
Carried interest	137	85
Total investments	378	371
Separate account assets	886	860
Total separate account collateral held under securities lending agreements	'	'
Other assets	'	'
Total	1,284	1,231
Separate account collateral liabilities under securities lending agreements	'	'
Other liabilities	'	'
Total liabilities measured at fair value	'	'
Fair Value, Measurements, Recurring [Member] | Other Assets Not Held at Fair Value [Member] | Variable Interest Entity, Primary Beneficiary, Aggregated Disclosure [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total assets of consolidated VIEs	20	'
Borrowings of consolidated VIEs	'	'
Fair Value, Measurements, Recurring [Member] | Other Assets Not Held at Fair Value [Member] | Equity Securities [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total available-for-sale	'	'
Total separate account collateral held under securities lending agreements	'	'
Fair Value, Measurements, Recurring [Member] | Other Assets Not Held at Fair Value [Member] | Debt Securities [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total available-for-sale	'	'
Held-to-maturity debt securities	57	112
Total separate account collateral held under securities lending agreements	'	'
Fair Value, Measurements, Recurring [Member] | Other Assets Not Held at Fair Value [Member] | Deferred Compensation Plan Mutual Funds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total trading	'	'
Fair Value, Measurements, Recurring [Member] | Other Assets Not Held at Fair Value [Member] | Equity/Multi-asset Mutual Funds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total trading	'	'
Fair Value, Measurements, Recurring [Member] | Other Assets Not Held at Fair Value [Member] | Debt Securities/ Fixed Income Mutual Fund [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total trading	'	'
Fair Value, Measurements, Recurring [Member] | Other Assets Not Held at Fair Value [Member] | Hedge Funds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total consolidated sponsored investment funds	'	'
Fair Value, Measurements, Recurring [Member] | Other Assets Not Held at Fair Value [Member] | Private/ Public Equity [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total consolidated sponsored investment funds	'	'
Fair Value, Measurements, Recurring [Member] | Other Assets Not Held at Fair Value [Member] | Private/ Public Equity [Member] | Variable Interest Entity, Primary Beneficiary, Aggregated Disclosure [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total assets of consolidated VIEs	'	'
Fair Value, Measurements, Recurring [Member] | Other Assets Not Held at Fair Value [Member] | Equity Method, Hedge Funds/Funds of Hedge Funds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total equity method	55	39
Fair Value, Measurements, Recurring [Member] | Other Assets Not Held at Fair Value [Member] | Equity Method, Private Equity Funds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total equity method	'	'
Fair Value, Measurements, Recurring [Member] | Other Assets Not Held at Fair Value [Member] | Equity Method, Real Estate Funds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total equity method	7	15
Fair Value, Measurements, Recurring [Member] | Other Assets Not Held at Fair Value [Member] | Fixed Income Mutual Securities [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total equity method	'	'
Fair Value, Measurements, Recurring [Member] | Other Assets Not Held at Fair Value [Member] | Equity Multi Asset Class Alternative Mutual Funds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total equity method	'	'
Fair Value, Measurements, Recurring [Member] | Other Assets Not Held at Fair Value [Member] | Bank Loans and Other Assets [Member] | Variable Interest Entity, Primary Beneficiary, Aggregated Disclosure [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total assets of consolidated VIEs	20	'
Fair Value, Measurements, Recurring [Member] | Other Assets Not Held at Fair Value [Member] | Bonds [Member] | Variable Interest Entity, Primary Beneficiary, Aggregated Disclosure [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total assets of consolidated VIEs	'	'

Fair_Value_Disclosures_Assets_1

Fair Value Disclosures - Assets and Liabilities Measured at Fair Value on Recurring Basis (Parenthetical) (Detail) (Fair Value, Measurements, Recurring [Member], Significant Unobservable Inputs (Level 3) [Member], USD $)	Sep. 30, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Third parties [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Private equity investments	$202	$212
Direct investments [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Private equity investments	32	54
Variable Interest Entity, Primary Beneficiary, Aggregated Disclosure [Member] | Third parties [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Assets of consolidated VIEs: Private / public equity	15	20
Variable Interest Entity, Primary Beneficiary, Aggregated Disclosure [Member] | Direct investments [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Assets of consolidated VIEs: Private / public equity	$2	$2

Fair_Value_Disclosures_Additio

Fair Value Disclosures - Additional Information (Detail) (USD $)

3 Months Ended

9 Months Ended

3 Months Ended

9 Months Ended

3 Months Ended

9 Months Ended

3 Months Ended

9 Months Ended

3 Months Ended

9 Months Ended

3 Months Ended

9 Months Ended

In Millions, unless otherwise specified

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Dec. 31, 2012

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Dec. 31, 2012

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2012

Separate account assets [Member]

Separate account assets [Member]

Separate account assets [Member]

Total Level 3 assets [Member]

Total Level 3 assets [Member]

Total Level 3 assets [Member]

Total Level 3 assets [Member]

Significant Unobservable Inputs (Level 3) [Member]

Significant Unobservable Inputs (Level 3) [Member]

Assets of Consolidated VIEs, bank loans [Member]

Assets of Consolidated VIEs, bank loans [Member]

Assets of Consolidated VIEs, bank loans [Member]

Assets of Consolidated VIEs, bank loans [Member]

Consolidated sponsored investment funds [Member]

CLO Borrowings [Member]

CLO Borrowings [Member]

CLO Borrowings [Member]

CLO Borrowings [Member]

Private/ Public Equity [Member]

Private/ Public Equity [Member]

CLO bank loans and bonds [Member]

CLO bank loans and bonds [Member]

CLO bank loans and bonds [Member]

CLO bank loans and bonds [Member]

Bank loans [Member]

Bank loans [Member]

Bank loans [Member]

Bank loans [Member]

Fair Value Disclosures [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Investments

'

'

'

'

'

'

'

'

'

'

$626

$679

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Private equity investments

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

34

56

'

'

'

'

Transfer into Level 3

'

'

'

34

'

48

'

'

'

'

'

'

40

36

71

89

'

'

'

'

'

'

'

'

'

'

'

Transfer out of Level 3

'

'

'

'

'

9

'

'

'

'

'

'

46

24

122

86

'

'

'

'

'

'

'

'

'

'

'

Transfers into Level 2

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

12

'

'

'

'

'

'

'

'

'

'

Distributions of earnings from equity method investees

'

39

29

'

'

'

17

24

37

57

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Settlements related to deconsolidation

'

134

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Reclassification of investment

'

28

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Settlements related to additional CLO

406

'

406

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Principal amounts outstanding of the borrowings, maturity year

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'2016

'

'

'

'

'

'

'

Principal amounts outstanding of the borrowings, maturity year

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'2025

'

'

'

'

'

'

'

Gains (loss) on fair value assets

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

25

45

104

123

Loss on fair value borrowings

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

$28

$44

$92

$118

'

'

'

'

'

'

Fair_Value_Disclosures_Changes

Fair Value Disclosures - Changes in Level 3 Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) (USD $)	3 Months Ended		9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Borrowings of consolidated VIEs [Member]	'	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'	'
Liabilities Measured at Fair Value, Beginning Balance	$2,145	$1,439	$2,402	$1,574
Realized and unrealized gains (losses) in earnings and OCI	-5	-27	-9	-66
Purchases	'	'	'	'
Sales and maturities	'	'	'	'
Issuances and other settlements	-82	377	-343	203
Transfers into Level 3	'	'	'	'
Transfers out of Level 3	'	'	'	'
Liabilities Measured at Fair Value, Ending Balance	2,068	1,843	2,068	1,843
Total net gains (losses) included in earnings	'	'	'	'
Other liabilities [Member]	'	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'	'
Liabilities Measured at Fair Value, Beginning Balance	'	'	'	'
Realized and unrealized gains (losses) in earnings and OCI	'	'	'	'
Purchases	'	'	'	'
Sales and maturities	'	'	'	'
Issuances and other settlements	33	'	33	'
Transfers into Level 3	'	'	'	'
Transfers out of Level 3	'	'	'	'
Liabilities Measured at Fair Value, Ending Balance	33	'	33	'
Total Level 3 liabilities [Member]	'	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'	'
Liabilities Measured at Fair Value, Beginning Balance	2,145	'	2,402	'
Realized and unrealized gains (losses) in earnings and OCI	-5	'	-9	'
Purchases	'	'	'	'
Sales and maturities	'	'	'	'
Issuances and other settlements	-49	'	-310	'
Transfers into Level 3	'	'	'	'
Transfers out of Level 3	'	'	'	'
Liabilities Measured at Fair Value, Ending Balance	2,101	'	2,101	'
Equity securities (CDOs) [Member]	'	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'	'
Assets Measured at Fair Value, Beginning Balance	1	1	1	1
Realized and unrealized gains (losses) in earnings and OCI	'	'	'	'
Purchases	'	'	'	'
Sales and maturities	'	'	'	'
Issuances and other settlements	'	'	'	'
Transfers into Level 3	'	'	'	'
Transfers out of Level 3	'	'	'	'
Assets Measured at Fair Value, Ending Balance	1	1	1	1
Total net gains (losses) included in earnings	'	'	'	'
Consolidated sponsored investment funds, Hedge funds / Funds of funds [Member]	'	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'	'
Assets Measured at Fair Value, Beginning Balance	47	46	73	22
Realized and unrealized gains (losses) in earnings and OCI	2	8	8	4
Purchases	'	3	12	30
Sales and maturities	-2	-2	-11	-2
Issuances and other settlements	-2	'	-30	-2
Transfers into Level 3	'	'	'	3
Transfers out of Level 3	'	'	-7	'
Assets Measured at Fair Value, Ending Balance	45	55	45	55
Total net gains (losses) included in earnings	'	8	6	4
Consolidated sponsored investment funds, Private equity [Member]	'	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'	'
Assets Measured at Fair Value, Beginning Balance	249	298	266	313
Realized and unrealized gains (losses) in earnings and OCI	10	22	26	43
Purchases	'	'	12	2
Sales and maturities	-23	-14	-62	-46
Issuances and other settlements	'	-8	'	-8
Transfers into Level 3	'	'	'	'
Transfers out of Level 3	-2	'	-8	-6
Assets Measured at Fair Value, Ending Balance	234	298	234	298
Total net gains (losses) included in earnings	7	20	21	38
Equity Method, Hedge Funds/Funds of Hedge Funds [Member]	'	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'	'
Assets Measured at Fair Value, Beginning Balance	157	187	161	193
Realized and unrealized gains (losses) in earnings and OCI	1	14	10	33
Purchases	1	'	2	'
Sales and maturities	-1	'	-1	'
Issuances and other settlements	-13	-21	-27	-46
Transfers into Level 3	'	'	'	'
Transfers out of Level 3	'	'	'	'
Assets Measured at Fair Value, Ending Balance	145	180	145	180
Total net gains (losses) included in earnings	1	14	10	33
Equity method, Private equity investments [Member]	'	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'	'
Assets Measured at Fair Value, Beginning Balance	105	88	90	85
Realized and unrealized gains (losses) in earnings and OCI	4	1	14	7
Purchases	1	1	10	4
Sales and maturities	-10	'	-10	'
Issuances and other settlements	-2	'	-6	-6
Transfers into Level 3	'	'	'	'
Transfers out of Level 3	'	'	'	'
Assets Measured at Fair Value, Ending Balance	98	90	98	90
Total net gains (losses) included in earnings	4	2	14	8
Equity Method, Real Estate Funds [Member]	'	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'	'
Assets Measured at Fair Value, Beginning Balance	97	101	88	88
Realized and unrealized gains (losses) in earnings and OCI	6	6	14	8
Purchases	2	6	5	19
Sales and maturities	'	-7	'	-7
Issuances and other settlements	-2	-3	-4	-5
Transfers into Level 3	'	'	'	'
Transfers out of Level 3	'	'	'	'
Assets Measured at Fair Value, Ending Balance	103	103	103	103
Total net gains (losses) included in earnings	6	4	14	6
Investments of consolidated funds [Member]	'	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'	'
Assets Measured at Fair Value, Beginning Balance	656	721	679	702
Realized and unrealized gains (losses) in earnings and OCI	23	51	72	95
Purchases	4	10	41	55
Sales and maturities	-36	-23	-84	-55
Issuances and other settlements	-19	-32	-67	-67
Transfers into Level 3	'	'	'	3
Transfers out of Level 3	-2	'	-15	-6
Assets Measured at Fair Value, Ending Balance	626	727	626	727
Total net gains (losses) included in earnings	18	48	65	89
Separate account assets [Member]	'	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'	'
Assets Measured at Fair Value, Beginning Balance	'	7	2	10
Realized and unrealized gains (losses) in earnings and OCI	'	-4	'	-5
Purchases	'	6	'	10
Sales and maturities	'	-7	-2	-18
Issuances and other settlements	'	'	'	'
Transfers into Level 3	'	34	'	48
Transfers out of Level 3	'	'	'	-9
Assets Measured at Fair Value, Ending Balance	'	36	'	36
Total net gains (losses) included in earnings	'	'	'	'
Assets of Consolidated VIEs, bank loans [Member]	'	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'	'
Assets Measured at Fair Value, Beginning Balance	93	85	106	83
Realized and unrealized gains (losses) in earnings and OCI	'	2	-1	2
Purchases	18	7	91	25
Sales and maturities	-8	-24	-48	-31
Issuances and other settlements	'	7	'	7
Transfers into Level 3	40	36	71	89
Transfers out of Level 3	-46	-24	-122	-86
Assets Measured at Fair Value, Ending Balance	97	89	97	89
Assets of consolidated VIEs, Bonds [Member]	'	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'	'
Assets Measured at Fair Value, Beginning Balance	35	44	46	40
Realized and unrealized gains (losses) in earnings and OCI	1	1	'	3
Purchases	'	'	4	2
Sales and maturities	-1	'	-15	'
Issuances and other settlements	'	'	'	'
Transfers into Level 3	'	'	'	'
Transfers out of Level 3	'	'	'	'
Assets Measured at Fair Value, Ending Balance	35	45	35	45
Consolidated VIEs, Private equity funds [Member]	'	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'	'
Assets Measured at Fair Value, Beginning Balance	19	25	22	27
Realized and unrealized gains (losses) in earnings and OCI	'	2	1	4
Purchases	'	2	'	2
Sales and maturities	-4	-3	-6	-7
Issuances and other settlements	'	'	'	'
Transfers into Level 3	'	'	'	'
Transfers out of Level 3	'	'	'	'
Assets Measured at Fair Value, Ending Balance	17	26	17	26
Assets of consolidated VIEs, Fund of hedge funds [Member]	'	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'	'
Assets Measured at Fair Value, Beginning Balance	'	'	'	'
Realized and unrealized gains (losses) in earnings and OCI	'	'	'	'
Purchases	'	'	134	'
Sales and maturities	'	'	'	'
Issuances and other settlements	'	'	-134	'
Transfers into Level 3	'	'	'	'
Transfers out of Level 3	'	'	'	'
Assets Measured at Fair Value, Ending Balance	'	'	'	'
Total net gains (losses) included in earnings	'	'	'	'
Total Level 3 assets of consolidated VIEs [Member]	'	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'	'
Assets Measured at Fair Value, Beginning Balance	147	154	174	150
Realized and unrealized gains (losses) in earnings and OCI	1	5	'	9
Purchases	18	9	229	29
Sales and maturities	-11	-27	-69	-38
Issuances and other settlements	'	7	-134	7
Transfers into Level 3	40	36	71	89
Transfers out of Level 3	-46	-24	-122	-86
Assets Measured at Fair Value, Ending Balance	149	160	149	160
Total net gains (losses) included in earnings	'	'	'	'
Total Level 3 assets [Member]	'	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'	'
Assets Measured at Fair Value, Beginning Balance	803	882	855	862
Realized and unrealized gains (losses) in earnings and OCI	24	52	72	99
Purchases	22	25	270	94
Sales and maturities	-47	-57	-155	-111
Issuances and other settlements	-19	-25	-201	-60
Transfers into Level 3	40	70	71	140
Transfers out of Level 3	-48	-24	-137	-101
Assets Measured at Fair Value, Ending Balance	$775	$923	$775	$923

Fair_Value_Disclosures_Fair_Va

Fair Value Disclosures - Fair Value of Financial Assets and Financial Liabilities (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2012	Dec. 31, 2011
In Millions, unless otherwise specified
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'
Cash and cash equivalents	$3,987	$4,606	$4,223	$3,506
Short-term borrowings	'	100	'	'
Long-term borrowings	4,938	5,687	'	'
Accounts receivable	4,311	2,250	'	'
Accounts payable and accrued liabilities	3,322	1,055	'	'
Estimated Fair Value [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'
Cash and cash equivalents	3,987	4,606	'	'
Cash and cash equivalents of consolidated VIEs	93	297	'	'
Short-term borrowings	'	100	'	'
Accounts receivable	4,311	2,250	'	'
Accounts payable and accrued liabilities	3,322	1,055	'	'
Estimated Fair Value [Member] | Significant Other Observable Inputs (Level 2) [Member]	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'
Long-term borrowings	5,310	6,275	'	'
Carrying Amount [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'
Cash and cash equivalents	3,987	4,606	'	'
Accounts receivable	4,311	2,250	'	'
Cash and cash equivalents of consolidated VIEs	93	297	'	'
Accounts payable and accrued liabilities	3,322	1,055	'	'
Short-term borrowings	'	100	'	'
Carrying Amount [Member] | Significant Other Observable Inputs (Level 2) [Member]	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'
Long-term borrowings	$4,938	$5,687	'	'

Fair_Value_Disclosures_Fair_Va1

Fair Value Disclosures - Fair Value of Financial Assets and Financial Liabilities (Parenthetical) (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2012	Dec. 31, 2011
In Millions, except Per Share data, unless otherwise specified
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'
Cash and cash equivalents	$3,987	$4,606	$4,223	$3,506
Consolidated sponsored investment funds [Member]	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'
Cash and cash equivalents	105	133	'	'
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'
Money market valuation floor	$1	'	'	'
Money market funds in cash and cash equivalents	$76	$98	'	'

Fair_Value_Disclosures_Investm

Fair Value Disclosures - Investments in Certain Entities Calculate Net Asset Value Per Share (Detail) (USD $)	9 Months Ended	12 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]	'	'
Fair Value	$718	$761
Total Unfunded Commitments	186	225
Consolidated sponsored investment funds, Private equity [Member]	'	'
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]	'	'
Fair Value	202	212
Total Unfunded Commitments	25	32
Redemption Notice Period, Not Redeemable	'n/r	'n/r
Consolidated Sponsored Investment Funds, Other funds of hedge funds [Member]	'	'
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]	'	'
Fair Value	57	98
Total Unfunded Commitments	'	'
Redemption Frequency (Not Redeemable)	72.00%	67.00%
Redemption Frequency (Monthly)	26.00%	22.00%
Redemption Frequency (Quarterly)	2.00%	11.00%
Redemption Notice Period, minimum, days	'2	'1
Redemption Notice Period, maximum, days	'90	'90
Equity Method, Hedge Funds/Funds of Hedge Funds [Member]	'	'
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]	'	'
Fair Value	212	222
Total Unfunded Commitments	92	42
Redemption Frequency (Not Redeemable)	66.00%	70.00%
Redemption Frequency (Monthly)	2.00%	2.00%
Redemption Frequency (Quarterly)	32.00%	28.00%
Redemption Notice Period, minimum, days	'15	'15
Redemption Notice Period, maximum, days	'90	'90
Equity Method, Private Equity Funds [Member]	'	'
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]	'	'
Fair Value	98	90
Total Unfunded Commitments	57	135
Redemption Notice Period, Not Redeemable	'n/r	'n/r
Equity Method, Real Estate Funds [Member]	'	'
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]	'	'
Fair Value	123	107
Total Unfunded Commitments	11	15
Redemption Frequency (Not Redeemable)	84.00%	82.00%
Redemption Frequency (Quarterly)	16.00%	18.00%
Redemption Notice Period, Not Redeemable	'60	'60
Equity method, Deferred compensation plan hedge fund investments [Member]	'	'
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]	'	'
Fair Value	11	9
Total Unfunded Commitments	'	'
Redemption Frequency (Monthly)	27.00%	33.00%
Redemption Frequency (Quarterly)	73.00%	67.00%
Redemption Notice Period, minimum, days	'60	'60
Redemption Notice Period, maximum, days	'90	'90
Consolidated VIEs, Private equity funds [Member]	'	'
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]	'	'
Fair Value	15	20
Total Unfunded Commitments	1	1
Redemption Notice Period, Not Redeemable	'n/r	'n/r
Trading equity [Member]	'	'
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]	'	'
Fair Value	'	3
Total Unfunded Commitments	'	'
Redemption Frequency (Daily)	'	100.00%

Fair_Value_Disclosures_Investm1

Fair Value Disclosures - Investments in Certain Entities Calculate Net Asset Value Per Share (Parenthetical) (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Consolidated sponsored investment funds, Private equity [Member]	'	'
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]	'	'
Liquidation period, years	'7 years	'7 years
Total remaining unfunded commitments to other third-parties, private equity funds	$25	$32
Amount of unfunded commitments contractually obligated to fund	30	30
Consolidated Sponsored Investment Funds, Other funds of hedge funds [Member]	'	'
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]	'	'
Redeemable period, maximum	'24 months	'24 months
Redeemable period, minimum	'12 months	'12 months
Equity Method, Hedge Funds/Funds of Hedge Funds [Member]	'	'
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]	'	'
Liquidation period, years	'4 years	'5 years
Equity Method, Private Equity Funds [Member]	'	'
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]	'	'
Liquidation period, years	'5 years	'5 years
Equity Method, Real Estate Funds [Member]	'	'
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]	'	'
Liquidation period, years	'7 years	'8 years
Consolidated VIEs, Private equity funds [Member]	'	'
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]	'	'
Liquidation period, years	'2 years	'3 years
Total remaining unfunded commitments to other third-parties, private equity funds	$1	$1

Fair_Value_Disclosures_Summary

Fair Value Disclosures - Summary of Information Related to Those Assets and Liabilities Selected for Fair Value Accounting (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Fair Value, Option, Quantitative Disclosures [Line Items]	'	'
Aggregate principal amounts outstanding	$4,950	'
Fair value	5,310	'
CLO Bank Loans [Member]	'	'
Fair Value, Option, Quantitative Disclosures [Line Items]	'	'
Aggregate principal amounts outstanding	1,976	2,124
Fair value	1,964	2,110
Aggregate unpaid principal balance in excess of/(less than) fair value	12	14
Unpaid principal balance of loans more than 90 days past due	12	4
Aggregate fair value of loans more than 90 days past due	7	'
Aggregate unpaid principal balance in excess of fair value for loans more than 90 days past due	5	4
CLO Borrowings [Member] | Variable Interest Entity, Primary Beneficiary, Aggregated Disclosure [Member]	'	'
Fair Value, Option, Quantitative Disclosures [Line Items]	'	'
Aggregate principal amounts outstanding	2,201	2,535
Fair value	$2,068	$2,402

Variable_Interest_Entities_Bal

Variable Interest Entities - Balances Relating to Variable Interest Entities in which BlackRock is Primary Beneficiary (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2012	Dec. 31, 2011
In Millions, unless otherwise specified
Variable Interest Entity [Line Items]	'	'	'	'
Cash and cash equivalents	$3,987	$4,606	$4,223	$3,506
Other liabilities	-948	-858	'	'
Nonredeemable noncontrolling interests	-127	-155	'	'
Consolidated Entity, Variable Interest Entities VIE [Member]	'	'	'	'
Variable Interest Entity [Line Items]	'	'	'	'
Cash and cash equivalents	93	297	'	'
Bank loans	1,964	2,110	'	'
Bonds	99	124	'	'
Other investments and other assets	44	30	'	'
Total bank loans, bonds, other investments and other assets	2,107	2,264	'	'
Borrowings	-2,068	-2,402	'	'
Other liabilities	-88	-103	'	'
Appropriated retained earnings	-25	-29	'	'
Nonredeemable noncontrolling interests	-19	-27	'	'
Total BlackRock net interests in consolidated VIEs	'	'	'	'

Variable_Interest_Entities_Add

Variable Interest Entities - Additional Information (Detail) (USD $)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012
Variable Interest Entity [Line Items]	'	'	'	'	'
Net gain (loss) attributable to nonredeemable non-controlling interests	($1,000,000)	$10,000,000	$11,000,000	$15,000,000	'
Consolidated Entity, Variable Interest Entities VIE [Member]	'	'	'	'	'
Variable Interest Entity [Line Items]	'	'	'	'	'
Net gain (loss) attributable to nonredeemable non-controlling interests	-6,000,000	2,000,000	-2,000,000	1,000,000	'
Nonoperating gain (loss)	-6,000,000	2,000,000	-2,000,000	1,000,000	'
Weighted-average maturities of bank loans and bonds, years	'	'	'4 years 8 months 12 days	'	'4 years 6 months
Nonconsolidated Entity Variable Interest Entities VIE [Member]	'	'	'	'	'
Variable Interest Entity [Line Items]	'	'	'	'	'
Other sponsored investments funds collective trusts	1,400,000,000,000	'	1,400,000,000,000	'	1,300,000,000,000
Nonconsolidated Entity Variable Interest Entities VIE [Member] | Minimum [Member]	'	'	'	'	'
Variable Interest Entity [Line Items]	'	'	'	'	'
Other sponsored investments funds	1,600,000,000,000	'	1,600,000,000,000	'	1,500,000,000,000
Nonconsolidated Entity Variable Interest Entities VIE [Member] | Maximum [Member]	'	'	'	'	'
Variable Interest Entity [Line Items]	'	'	'	'	'
Other sponsored investments funds	$1,700,000,000,000	'	$1,700,000,000,000	'	1,600,000,000,000

Variable_Interest_Entities_Bal1

Variable Interest Entities - Balances Relating to Variable Interest Entities in which BlackRock is Not Primary Beneficiary (Detail) (Nonconsolidated Entity Variable Interest Entities VIE [Member], USD $)	Sep. 30, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Investments [Member]	'	'
Variable Interest Entity [Line Items]	'	'
CDOs/CLOs	$1	$1
Collective trusts	'	'
Other	18	17
Total	19	18
Advisory Fee Receivables [Member]	'	'
Variable Interest Entity [Line Items]	'	'
CDOs/CLOs	1	1
Collective trusts	166	248
Other	130	61
Total	297	310
Other Net Assets (Liabilities) [Member]	'	'
Variable Interest Entity [Line Items]	'	'
CDOs/CLOs	-4	-5
Collective trusts	'	'
Other	-5	-3
Total	-9	-8
Maximum Risk of Loss [Member]	'	'
Variable Interest Entity [Line Items]	'	'
CDOs/CLOs	19	19
Collective trusts	166	248
Other	148	77
Total	$333	$344

Variable_Interest_Entities_Bal2

Variable Interest Entities - Balances Relating to Variable Interest Entities in which BlackRock is Not Primary Beneficiary (Parenthetical) (Detail) (Nonconsolidated Entity Variable Interest Entities VIE [Member], USD $)	9 Months Ended	12 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Nonconsolidated Entity Variable Interest Entities VIE [Member]	'	'
Variable Interest Entity [Line Items]	'	'
Credit protection	$17	$17

Variable_Interest_Entities_Unc

Variable Interest Entities - Unconsolidated Collateralized Debt or Loan Obligations and Other Sponsored Investment Funds (Detail) (Nonconsolidated Entity Variable Interest Entities VIE [Member], USD $)	Sep. 30, 2013	Dec. 31, 2012
In Billions, unless otherwise specified
Nonconsolidated Entity Variable Interest Entities VIE [Member]	'	'
Variable Interest Entity [Line Items]	'	'
Assets at fair value	$3	$4
Liabilities	5	5
Net assets	($2)	($1)

Derivatives_and_Hedging_Additi

Derivatives and Hedging - Additional Information (Detail) (USD $)	9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	31-May-11	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2013	Sep. 30, 2013	Dec. 31, 2012	31-May-11
			Total return swap [Member]	Total return swap [Member]	Interest rate swap [Member]	Foreign exchange future [Member]	Foreign exchange future [Member]	Cash flow hedging [Member]
								Interest rate swap [Member]
Derivative [Line Items]	'	'	'	'	'	'	'	'
Notional value	'	'	$113	$206	$68	$680	$79	$750
Credit default swap maximum risk of loss for credit protection	$17	'	'	'	'	'	'	'
Interest on this swap, fixed rate	'	1.03%	'	'	'	'	'	'
Interest on swap commencement and semi-annual payment dates	'May 24 and November 24 of each year	'	'	'	'	'	'	'

Goodwill_Goodwill_Activity_Det

Goodwill - Goodwill Activity (Detail) (USD $)	9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013
Goodwill [Abstract]	'
Beginning balance	$12,910
Acquisition	44
Goodwill adjustment related to Quellos and other	-16
Ending balance	$12,938

Goodwill_Goodwill_Activity_Par

Goodwill - Goodwill Activity (Parenthetical) (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012	Jul. 01, 2013
In Millions, unless otherwise specified			Credit Suisse ETF Franchise [Member]
Goodwill [Line Items]	'	'	'
Purchase price	'	'	$273
Excess of tax goodwill over book goodwill	$301	$324	'

Intangible_Assets_Carrying_Amo

Intangible Assets - Carrying Amounts of Identifiable Intangible Assets (Detail) (USD $)	3 Months Ended		9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Intangible Assets [Line Items]	'	'	'	'
Intangible assets, Beginning balance	'	'	$17,402	'
Acquisition	'	'	231	'
Amortization expense	-40	-39	-120	-117
Intangible assets, Ending balance	17,513	'	17,513	'
Indefinite-lived intangible assets [Member]	'	'	'	'
Intangible Assets [Line Items]	'	'	'	'
Intangible assets, Beginning balance	'	'	16,760	'
Acquisition	'	'	231	'
Amortization expense	'	'	0	'
Intangible assets, Ending balance	16,991	'	16,991	'
Finite-lived intangible assets [Member]	'	'	'	'
Intangible Assets [Line Items]	'	'	'	'
Intangible assets, Beginning balance	'	'	642	'
Acquisition	'	'	0	'
Amortization expense	'	'	-120	'
Intangible assets, Ending balance	$522	'	$522	'

Other_Assets_Additional_Inform

Other Assets - Additional Information (Detail) (USD $)	9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013
Other Assets [Line Items]	'
Gain related to PennyMac initial public offering	$39
Charitable contribution	124
Gain related to the Charitable Contribution	80
Tax benefit related to Charitable Contribution	57
Pennymac [Member]	'
Other Assets [Line Items]	'
Gain related to PennyMac initial public offering	39
Charitable Contribution, by units	6.1
Charitable contribution	124
Gain related to the Charitable Contribution	80
Tax benefit related to Charitable Contribution	57
PennyMac ownership percentage	20.00%
Remaining units in PennyMac	16
Carrying value - equity method investment	120
Fair value of equity method investments	$292

Borrowings_Additional_Informat

Borrowings - Additional Information (Detail) (USD $)	9 Months Ended		1 Months Ended	3 Months Ended
	Sep. 30, 2013	Dec. 31, 2012	31-May-13	Mar. 31, 2013
			Two-year floating rate notes [Member]	2013 Revolving Credit Facility [Member]
Debt Instrument [Line Items]	'	'	'	'
Additional amount available, subject to lender credit approval	'	'	'	$1,000,000,000
Extended debt instrument maturity date	'	'	'	'March 2018
Unsecured revolving credit facility	3,990,000,000	'	'	3,990,000,000
Maximum amount available under facility	'	'	'	4,990,000,000
Line of credit facility, covenant terms	'The 2013 credit facility requires the Company not to exceed a maximum leverage ratio (ratio of net debt to earnings before interest, taxes, depreciation and amortization, where net debt equals total debt less unrestricted cash)	'	'	'
Line of credit facility, covenant compliance	'Satisfied with a ratio of less than 1 to 1 at September 30, 2013	'	'	'
Repayment of long term borrowings	'	'	750,000,000	'
Long-term borrowings	4,938,000,000	5,687,000,000	'	'
Long-term debt, fair value	'	$6,275,000,000	'	'

Borrowings_Carrying_Value_and_

Borrowings - Carrying Value and Fair Value of Long-Term Borrowings (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Debt Instrument [Line Items]	'	'
Maturity Amount	$4,950	'
Unamortized Discount	-12	'
Carrying Value	4,938	5,687
Fair value	5,310	'
3.50% Notes due 2014 [Member]	'	'
Debt Instrument [Line Items]	'	'
Maturity Amount	1,000	'
Unamortized Discount	'	'
Carrying Value	1,000	'
Fair value	1,036	'
1.375% Notes due 2015 [Member]	'	'
Debt Instrument [Line Items]	'	'
Maturity Amount	750	'
Unamortized Discount	'	'
Carrying Value	750	'
Fair value	762	'
6.25% Notes due 2017 [Member]	'	'
Debt Instrument [Line Items]	'	'
Maturity Amount	700	'
Unamortized Discount	-2	'
Carrying Value	698	'
Fair value	818	'
5.00% Notes due 2019 [Member]	'	'
Debt Instrument [Line Items]	'	'
Maturity Amount	1,000	'
Unamortized Discount	-2	'
Carrying Value	998	'
Fair value	1,147	'
4.25% Notes due 2021 [Member]	'	'
Debt Instrument [Line Items]	'	'
Maturity Amount	750	'
Unamortized Discount	-4	'
Carrying Value	746	'
Fair value	798	'
3.375% Notes due 2022 [Member]	'	'
Debt Instrument [Line Items]	'	'
Maturity Amount	750	'
Unamortized Discount	-4	'
Carrying Value	746	'
Fair value	$749	'

Commitments_and_Contingencies_

Commitments and Contingencies - Additional Information (Detail) (USD $)	9 Months Ended
	Sep. 30, 2013
Commitments And Contingencies Disclosure [Abstract]	'
Investment commitments relating primarily to funds of private equity funds, real estate funds and hedge funds	$216,000,000
Credit default swap maximum risk of loss for credit protection	17,000,000
Fee measurement period	'7 years
Loan balances	115,000,000,000
Collateral for indemnified securities	$121,000,000,000

StockBased_Compensation_Restri

Stock-Based Compensation - Restricted Stock and Restricted Stock Units ("RSUs") Activity (Detail) (USD $)	1 Months Ended	9 Months Ended
	Jan. 31, 2013	Sep. 30, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Restricted Stock and RSUs, beginning of period	5,620,835	5,620,835
Granted, Restricted Stock and RSUs	'	1,645,277
Converted, Restricted Stock and RSUs	'	-2,502,869
Forfeited, Restricted Stock and RSUs	'	-70,491
Restricted Stock and RSUs, end of period	'	4,692,752
Weighted-Average Grant Date Fair Value, beginning of period	$197.90	$197.90
Granted, Weighted-Average Grant Date Fair Value	'	$234.69
Converted, Weighted-Average Grant Date Fair Value	'	$204.46
Forfeited, Weighted-Average Grant Date Fair Value	'	$204.41
Weighted-Average Grant Date Fair Value, end of period	'	$207.20
Market Performance-Based RSUs [Member]	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Restricted Stock and RSUs, beginning of period	575,532	575,532
Granted, Restricted Stock and RSUs	556,581	556,581
Restricted Stock and RSUs, end of period	'	1,132,113
Weighted-Average Grant Date Fair Value, beginning of period	$115.03	$115.03
Granted, Weighted-Average Grant Date Fair Value	'	$126.76
Weighted-Average Grant Date Fair Value, end of period	'	$120.80

StockBased_Compensation_Restri1

Stock-Based Compensation - Restricted Stock and Restricted Stock Units ("RSUs") Activity (Parenthetical) (Detail)	Sep. 30, 2013
In Millions, unless otherwise specified
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'
Share-based compensation awards expected to vest	4.4
Awards vested, not converted	0.3
Market Performance-Based RSUs [Member]	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'
Share-based compensation awards expected to vest	1.1
Awards vested, not converted	0

StockBased_Compensation_Additi

Stock-Based Compensation - Additional Information (Detail) (USD $)	1 Months Ended	9 Months Ended	1 Months Ended		9 Months Ended	1 Months Ended	12 Months Ended		9 Months Ended
	Jan. 31, 2013	Sep. 30, 2013	Jan. 31, 2013	Jan. 31, 2013	Sep. 30, 2013	Jan. 31, 2013	Dec. 31, 2012	Sep. 30, 2013	Sep. 30, 2013
			Restricted Stock And RSUs [Member]	Market Performance-Based RSUs [Member]	Market Performance-Based RSUs [Member]	Long-Term Incentive Plans Funded by PNC [Member]	Long-Term Incentive Plans Funded by PNC [Member]	Long-Term Incentive Plans Funded by PNC [Member]	Unvested market performance-based awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'	'	'	'	'	'	'
Granted, Restricted Stock and Units	'	1,645,277	1,172,381	556,581	556,581	'	'	'	'
Vesting period	'	'	'3 years	'	'	'	'	'	'
Awards to employees cliff vesting	370,812	'	'	'	'	'	'	'	'
RSUs to employees that cliff vest, percentage	100.00%	'	'	'	'	'	'	'	'
RSUs to employees that cliff vest, date	31-Jan-16	'	'	'	'	'	'	'	'
Intrinsic value of outstanding RSUs	'	$1,300,000,000	'	'	'	'	'	'	'
BlackRock's closing stock price	'	270.62	'	'	'	'	'	'	'
Unrecognized stock-based compensation expenses	'	348,000,000	'	'	'	'	'	'	96,000,000
Weighted-average period	'	'10 months 24 days	'	'	'	'	'	'	'
Remaining weighted-average period	'	'	'	'	'	'	'	'	'2 years 9 months 18 days
Shares committed to fund long-term incentive plans	'	'	'	'	'	'	'	4,000,000	'
Number of additional shares surrendered	'	'	'	'	'	200,000	2,500,000	'	'
Remaining shares committed by PNC for long-term incentive awards	'	'	'	'	'	'	'	1,300,000	'
Aggregate intrinsic value of options exercised	'	$8,300,000	'	'	'	'	'	'	'

StockBased_Compensation_Stock_

Stock-Based Compensation - Stock Option Activity (Detail) (USD $)	9 Months Ended
	Sep. 30, 2013
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]	'
Outstanding, Shares Under Option, beginning of period	1,099,909
Exercised, Shares Under Option	-85,090
Outstanding, Shares Under Option, end of period	1,014,819
Outstanding at beginning of period, Weighted-Average Exercise Price	$167.76
Exercised, Weighted-Average Exercise Price	$167.76
Outstanding at end of period, Weighted-Average Exercise Price	$167.76

Net_Capital_Requirements_Addit

Net Capital Requirements - Additional Information (Detail) (USD $)	Sep. 30, 2013
In Billions, unless otherwise specified
Banking And Thrift [Abstract]	'
Net capital requirement in certain regulated subsidiaries	$1.10

Accumulated_Other_Comprehensiv2

Accumulated Other Comprehensive Income (Loss) - Changes in Accumulated Other Comprehensive Income (Detail) (USD $)	3 Months Ended		9 Months Ended		3 Months Ended	9 Months Ended				3 Months Ended	9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2013	Sep. 30, 2013	Jul. 01, 2013	Dec. 31, 2012	Sep. 30, 2013	Sep. 30, 2013
					Unrealized gains (losses) on available-for-sale investments [Member]	Unrealized gains (losses) on available-for-sale investments [Member]	Benefit plans [Member]	Benefit plans [Member]	Benefit plans [Member]	Foreign currency translation adjustments [Member]	Foreign currency translation adjustments [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]	'	'	'	'	'	'	'	'	'	'	'
Beginning Balance	($198)	'	($59)	'	$8	$16	($4)	($4)	($4)	($202)	($71)
Other comprehensive income (loss) before reclassifications	120	'	-10	'	2	3	'	'	'	118	-13
Amount reclassified from AOCI	-1	'	-10	'	-1	-10	'	'	'	'	'
Net other comprehensive income (loss)	119	68	-20	69	1	-7	'	'	'	118	-13
Ending Balance	($79)	'	($79)	'	$9	$9	($4)	($4)	($4)	($84)	($84)

Capital_Stock_Preferred_Shares

Capital Stock - Preferred Shares Authorized, Issued and Outstanding (Detail)	Sep. 30, 2013	Dec. 31, 2012
Series A Nonvoting Participating Preferred Stock [Member]	'	'
Schedule of Capitalization, Equity [Line Items]	'	'
Shares authorized, $0.01 par value	20,000,000	20,000,000
Shares issued and outstanding	'	'
Series B Nonvoting Participating Preferred Stock [Member]	'	'
Schedule of Capitalization, Equity [Line Items]	'	'
Shares authorized, $0.01 par value	150,000,000	150,000,000
Shares issued and outstanding	823,188	823,188
Series C Nonvoting Participating Preferred Stock [Member]	'	'
Schedule of Capitalization, Equity [Line Items]	'	'
Shares authorized, $0.01 par value	6,000,000	6,000,000
Shares issued and outstanding	1,311,887	1,517,237
Series D Nonvoting Participating Preferred Stock [Member]	'	'
Schedule of Capitalization, Equity [Line Items]	'	'
Shares authorized, $0.01 par value	20,000,000	20,000,000
Shares issued and outstanding	'	'

Capital_Stock_Preferred_Shares1

Capital Stock - Preferred Shares Authorized, Issued and Outstanding (Parenthetical) (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
Series A Nonvoting Participating Preferred Stock [Member]	'	'
Schedule of Capitalization, Equity [Line Items]	'	'
Preferred stock, par value	$0.01	$0.01
Series B Nonvoting Participating Preferred Stock [Member]	'	'
Schedule of Capitalization, Equity [Line Items]	'	'
Preferred stock, par value	$0.01	$0.01
Series C Nonvoting Participating Preferred Stock [Member]	'	'
Schedule of Capitalization, Equity [Line Items]	'	'
Preferred stock, par value	$0.01	$0.01
Series D Nonvoting Participating Preferred Stock [Member]	'	'
Schedule of Capitalization, Equity [Line Items]	'	'
Preferred stock, par value	$0.01	$0.01

Capital_Stock_Additional_Infor

Capital Stock - Additional Information (Detail) (USD $)	9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Jan. 31, 2013
Statement Of Stockholders Equity [Abstract]	'	'
Share repurchase program authorized shares	'	10.2
Common shares repurchased	2.9	'
Common shares repurchased, value	$750	'
Shares authorized to be repurchased	7.3	'

Earnings_Per_Share_Computation

Earnings Per Share - Computation of Basic and Diluted EPS under Treasury Stock Method and Two-Class Method (Detail) (USD $)	3 Months Ended		9 Months Ended
In Millions, except Share data, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Earnings Per Share [Abstract]	'	'	'	'
Net income attributable to BlackRock	$730	$642	$2,091	$1,768
Basic weighted-average shares outstanding	169,811,633	172,359,141	170,581,930	176,116,975
Dilutive effect of nonparticipating RSUs and stock options	3,559,875	3,091,391	3,430,946	2,839,724
Total diluted weighted-average shares outstanding	173,371,508	175,450,532	174,012,876	178,956,699
Basic earnings per share	$4.30	$3.72	$12.26	$10.02
Diluted earnings per share	$4.21	$3.65	$12.02	$9.87
Less: Dividends distributed to common shares	'	259	'	803
Less: Dividends distributed to participating RSUs	'	'	'	1
Undistributed net income attributable to BlackRock	'	383	'	964
Percentage of undistributed net income allocated to common shares	'	99.90%	'	99.90%
Undistributed net income allocated to common shares	'	382	'	963
Net income attributable to common shares	'	$641	'	$1,766

Earnings_Per_Share_Computation1

Earnings Per Share - Computation of Basic and Diluted EPS under Treasury Stock Method and Two-Class Method (Parenthetical) (Detail)	3 Months Ended	9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2012	Sep. 30, 2012
Earnings Per Share [Abstract]	'	'
Unvested RSUs included in participating securities that contain nonforfeitable rights to dividends	0.2	0.2

Income_Taxes_Additional_Inform

Income Taxes - Additional Information (Detail) (USD $)	3 Months Ended		9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Income Tax Disclosure [Abstract]	'	'	'	'
Net noncash tax benefit	$64	$30	$64	$30
Tax benefit related to Charitable Contribution	'	'	57	'
Tax benefit primarily due to the realization of loss carryforwards	$29	'	$29	'

Segment_Information_Schedule_o

Segment Information - Schedule of Investment Advisory, Administration Fees, Securities Lending Revenue and Performance Fees, BlackRock Solutions and Advisory Revenue, Distribution Fees and Other Revenue (Detail) (USD $)	3 Months Ended		9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Segment Reporting Information [Line Items]	'	'	'	'
Revenue	$2,472	$2,320	$7,403	$6,798
BlackRock Solutions and advisory	156	128	420	382
Distribution fees	19	19	54	58
Other revenue	48	46	177	143
Investment Advisory, Administration Fees And Securities Lending Revenue [Member]	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Revenue	2,249	2,127	6,752	6,215
Investment Advisory, Administration Fees And Securities Lending Revenue [Member] | Equity [Member]	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Revenue	1,170	1,073	3,525	3,196
Investment Advisory, Administration Fees And Securities Lending Revenue [Member] | Fixed income [Member]	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Revenue	490	491	1,488	1,386
Investment Advisory, Administration Fees And Securities Lending Revenue [Member] | Multi-asset [Member]	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Revenue	266	241	777	724
Investment Advisory, Administration Fees And Securities Lending Revenue [Member] | Alternatives [Member]	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Revenue	248	232	718	642
Investment Advisory, Administration Fees And Securities Lending Revenue [Member] | Cash management [Member]	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Revenue	75	90	244	267
BlackRock Solutions And Advisory [Member]	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
BlackRock Solutions and advisory	156	128	420	382
Distribution Fees [Member]	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Distribution fees	19	19	54	58
Other Segments [Member]	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Other revenue	$48	$46	$177	$143

Segment_Information_Total_Reve

Segment Information - Total Revenue by Geographic Region (Detail) (USD $)	3 Months Ended		9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Segment Reporting Information [Line Items]	'	'	'	'
Revenue	$2,472	$2,320	$7,403	$6,798
Americas [Member]	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Revenue	1,632	1,578	4,967	4,676
Europe [Member]	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Revenue	726	629	2,060	1,795
Asia-Pacific [Member]	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Revenue	$114	$113	$376	$327

Segment_Information_Schedule_o1

Segment Information - Schedule of Long-Lived Assets by Geographic Region (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Segment Reporting Information [Line Items]	'	'
Long-lived assets	$13,461	$13,467
Americas [Member]	'	'
Segment Reporting Information [Line Items]	'	'
Long-lived assets	13,197	13,238
Europe [Member]	'	'
Segment Reporting Information [Line Items]	'	'
Long-lived assets	207	166
Asia-Pacific [Member]	'	'
Segment Reporting Information [Line Items]	'	'
Long-lived assets	$57	$63