Alliancebernstein 10-Q 30 Apr 15 2015 Q1 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	3 Months Ended
	Mar. 31, 2015
Document and Entity Information [Abstract]
Entity Registrant Name	ALLIANCEBERNSTEIN L.P.
Entity Central Index Key	1109448
Current Fiscal Year End Date	-19
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Non-accelerated Filer
Entity Common Stock, Shares Outstanding	272,607,593
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	Q1
Document Type	10-Q
Amendment Flag	FALSE
Document Period End Date	31-Mar-15

Condensed_Consolidated_Stateme

Condensed Consolidated Statements of Financial Condition (unaudited) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
ASSETS
Cash and cash equivalents	$671,288	$555,503
Cash and securities segregated, at fair value (cost: $520,133 and $476,275)	520,139	476,277
Receivables, net:
Brokers and dealers	413,009	378,467
Brokerage clients	1,325,185	1,243,667
Fees	273,073	292,901
Investments:
Long-term incentive compensation-related	80,546	98,779
Other	648,205	664,696
Furniture, equipment and leasehold improvements, net	158,041	160,956
Goodwill	3,044,807	3,044,807
Intangible assets, net	165,310	171,407
Deferred sales commissions, net	121,882	118,290
Other assets	190,000	172,703
Total assets	7,611,485	7,378,453
Payables:
Brokers and dealers	330,332	302,484
Securities sold not yet purchased	66,904	88,902
Brokerage clients	1,683,433	1,501,227
AB mutual funds	109,264	141,132
Accounts payable and accrued expenses	469,896	432,355
Accrued compensation and benefits	363,928	291,000
Debt	500,582	488,988
Total liabilities	3,524,339	3,246,088
Commitments and contingencies (See Note 12)
Redeemable non-controlling interest	16,504	16,504
Capital:
General Partner	40,932	41,381
Limited partners: 272,607,593 and 273,040,452 units issued and outstanding	4,132,523	4,176,637
Receivables from affiliates	-10,051	-16,359
AB Holding Units held for long-term incentive compensation plans	-33,001	-36,351
Accumulated other comprehensive loss	-91,568	-79,843
Partners' capital attributable to AB Unitholders	4,038,835	4,085,465
Non-controlling interests in consolidated entities	31,807	30,396
Total capital	4,070,642	4,115,861
Total liabilities, redeemable non-controlling interest and capital	$7,611,485	$7,378,453

Condensed_Consolidated_Stateme1

Condensed Consolidated Statements of Financial Condition (unaudited) (Parenthetical) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, except Share data, unless otherwise specified
ASSETS
Cash and securities segregated, at cost	$520,133	$476,275
Capital:
Limited partners, units issued (in units)	272,607,593	273,040,452
Limited partners, units outstanding (in units)	272,607,593	273,040,452

Condensed_Consolidated_Stateme2

Condensed Consolidated Statements of Income (unaudited) (USD $)	3 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Revenues:
Investment advisory and services fees	$493,988	$454,884
Bernstein research services	126,046	123,009
Distribution revenues	109,184	106,186
Dividend and interest income	5,094	4,101
Investment gains (losses)	3,888	559
Other revenues	24,990	26,680
Total revenues	763,190	715,419
Less: Interest expense	619	801
Net revenues	762,571	714,618
Expenses:
Employee compensation and benefits	326,327	307,033
Promotion and servicing:
Distribution-related payments	100,386	98,642
Amortization of deferred sales commissions	12,399	8,957
Other	55,537	53,645
General and administrative:
General and administrative	107,333	107,487
Real estate (credits) charges	-383	1,942
Contingent payment arrangements	443	321
Interest on borrowings	854	781
Amortization of intangible assets	6,461	5,907
Total expenses	609,357	584,715
Operating income	153,214	129,903
Income taxes	10,470	11,365
Net income	142,744	118,538
Net income of consolidated entities attributable to non-controlling interests	1,275	1,813
Net income attributable to AB Unitholders	$141,469	$116,725
Net income per AB Unit:
Basic (in dollars per share)	$0.51	$0.43
Diluted (in dollars per share)	$0.51	$0.43

Condensed_Consolidated_Stateme3

Condensed Consolidated Statements of Comprehensive Income (unaudited) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Condensed Consolidated Statements of Comprehensive Income (unaudited) [Abstract]
Net income	$142,744	$118,538
Other comprehensive income (loss):
Foreign currency translation adjustments	-12,275	2,149
Income tax expense	0	0
Foreign currency translation adjustments, net of tax	-12,275	2,149
Unrealized gains on investments:
Unrealized gains arising during period	189	428
Less: reclassification adjustment for (losses) included in net income	0	-4
Change in unrealized gains on investments	189	432
Income tax benefit (expense)	119	-143
Unrealized gains on investments, net of tax	308	289
Changes in employee benefit related items:
Amortization of prior service cost	0	-1,299
Recognized actuarial gain	237	486
Changes in employee benefit related items	237	-813
Income tax expense	-62	-20
Employee benefit related items, net of tax	175	-833
Other comprehensive (loss) income	-11,792	1,605
Less: Comprehensive income in consolidated entities attributable to non-controlling interests	1,208	1,854
Comprehensive income attributable to AB Unitholders	$129,744	$118,289

Condensed_Consolidated_Stateme4

Condensed Consolidated Statements of Cash Flows (unaudited) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Cash flows from operating activities:
Net income	$142,744	$118,538
Adjustments to reconcile net income to net cash provided by operating activities:
Amortization of deferred sales commissions	12,399	8,957
Non-cash long-term incentive compensation expense	3,387	6,101
Depreciation and other amortization	14,294	16,206
Unrealized (gains) on investments	-7,541	-2,499
Other, net	578	-171
Changes in assets and liabilities:
(Increase) decrease in segregated cash and securities	-43,862	80,737
(Increase) in receivables	-125,720	-125,446
Decrease in investments	42,310	11,473
(Increase) in deferred sales commissions	-15,991	-9,815
(Increase) in other assets	-18,756	-33,991
Increase in payables	181,581	24,294
Increase in accounts payable and accrued expenses	988	2,652
Increase in accrued compensation and benefits	73,370	29,654
Net cash provided by operating activities	259,781	126,690
Cash flows from investing activities:
Purchases of investments	-85	-190
Proceeds from sales of investments	0	42
Purchases of furniture, equipment and leasehold improvements	-5,050	-4,345
Proceeds from sales of furniture, equipment and leasehold improvements	33	23
Net cash used in investing activities	-5,102	-4,470
Cash flows from financing activities:
Issuance of commercial paper, net	11,295	104,497
Increase (decrease) in overdrafts payable	38,772	-41,517
Distributions to General Partner and Unitholders	-173,075	-178,994
Contributions from non-controlling interests in consolidated entities	202	0
Capital contributions from General Partner	335	437
Capital contributions from AB Holding	6,019	5,798
Payment for contingent payment arrangements	-213	-517
Additional investments by AB Holding with proceeds from exercise of compensatory options to buy AB Holding Units	3,901	4,656
Purchases of AB Holding Units to fund long-term incentive compensation plan awards, net	-16,929	-3,385
Purchases of AB Units	-11	-229
Other	-7	-9
Net cash used in financing activities	-129,711	-109,263
Effect of exchange rate changes on cash and cash equivalents	-9,183	2,271
Net increase in cash and cash equivalents	115,785	15,228
Cash and cash equivalents as of beginning of the period	555,503	509,891
Cash and cash equivalents as of end of the period	$671,288	$525,119

Business_Description_Organizat

Business Description, Organization and Basis of Presentation	3 Months Ended
	Mar. 31, 2015
Business Description, Organization and Basis of Presentation [Abstract]
Business Description, Organization and Basis of Presentation	1	Business Description, Organization and Basis of Presentation
	Business Description
	We provide research, diversified investment management and related services globally to a broad range of clients. Our principal services include:
		●	Institutional Services – servicing our institutional clients, including private and public pension plans, foundations and endowments, insurance companies, central banks and governments worldwide, and affiliates such as AXA and its subsidiaries, by means of separately-managed accounts, sub-advisory relationships, structured products, collective investment trusts, mutual funds, hedge funds and other investment vehicles.
		●	Retail Services – servicing our retail clients, primarily by means of retail mutual funds sponsored by AB or an affiliated company, sub-advisory relationships with mutual funds sponsored by third parties, separately-managed account programs sponsored by financial intermediaries worldwide and other investment vehicles.
		●	Private Wealth Management Services – servicing our private clients, including high-net-worth individuals and families, trusts and estates, charitable foundations, partnerships, private and family corporations, and other entities (including most institutions for which we manage accounts with less than $25 million in assets), by means of separately-managed accounts, hedge funds, mutual funds and other investment vehicles.
		●	Bernstein Research Services – servicing institutional investors, such as pension fund, hedge fund and mutual fund managers, seeking high-quality fundamental research, quantitative services and brokerage-related services in equities and listed options.
	We also provide distribution, shareholder servicing, transfer agency services and administrative services to the mutual funds we sponsor.
	Our high-quality, in-depth research is the foundation of our business.  Our research disciplines include economic, fundamental equity, fixed income and quantitative research.  In addition, we have experts focused on multi-asset strategies, wealth management and alternative investments.
	We provide a broad range of investment services with expertise in:
		●	Actively managed equity strategies, with global and regional portfolios across capitalization ranges and investment strategies, including value, growth and core equities;
		●	Actively managed traditional and unconstrained fixed income strategies, including taxable and tax-exempt strategies;
		●	Passive management, including index and enhanced index strategies;
		●	Alternative investments, including hedge funds, fund of funds and private equity (e.g., direct real estate investing); and
		●	Multi-asset solutions and services, including dynamic asset allocation, customized target-date funds and target-risk funds.
	Our services span various investment disciplines, including market capitalization (e.g., large-, mid- and small-cap equities), term (e.g., long-, intermediate- and short-duration debt securities), and geographic location (e.g., U.S., international, global, emerging markets, regional and local), in major markets around the world.
	Organization
	As of March 31, 2015, AXA, a société anonyme organized under the laws of France and the holding company for an international group of insurance and related financial services companies, through certain of its subsidiaries (“AXA and its subsidiaries”), owned approximately 1.4% of the issued and outstanding units representing assignments of beneficial ownership of limited partnership interests in AllianceBernstein Holding L.P. (“AB Holding Units”).
	As of March 31, 2015, the ownership structure of AB, expressed as a percentage of general and limited partnership interests, was as follows:
	AXA and its subsidiaries			62.2	%
	AB Holding			36.4
	Unaffiliated holders			1.4
				100	%
	AllianceBernstein Corporation (an indirect wholly-owned subsidiary of AXA, “General Partner”) is the general partner of both AllianceBernstein Holding L.P. (“AB Holding”) and AB. AllianceBernstein Corporation owns 100,000 general partnership units in AB Holding and a 1% general partnership interest in AB. Including both the general partnership and limited partnership interests in AB Holding and AB, AXA and its subsidiaries had an approximate 62.7% economic interest in AB as of March 31, 2015.
	Basis of Presentation
	The interim condensed consolidated financial statements have been prepared in accordance with the instructions to Form 10-Q pursuant to the rules and regulations of the U.S. Securities and Exchange Commission (“SEC”). In the opinion of management, all adjustments, consisting only of normal recurring adjustments, necessary for a fair statement of the interim results, have been made. The preparation of the condensed consolidated financial statements requires management to make certain estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the dates of the condensed consolidated financial statements and the reported amounts of revenues and expenses during the interim reporting periods. Actual results could differ from those estimates. The December 31, 2014 condensed consolidated statement of financial condition was derived from audited financial statements but does not include all disclosures required by accounting principles generally accepted in the United States of America.
	The condensed consolidated financial statements include AB and its majority-owned and/or controlled subsidiaries. All significant inter-company transactions and balances among the consolidated entities have been eliminated.
	Reclassification
	The first quarter 2014 amounts for Institutional and Private Wealth Management finders’ fees previously presented as other promotion and servicing are now presented as distribution-related payments in the condensed consolidated statements of income to conform to the current year’s presentation.

Accounting_Pronouncements

Accounting Pronouncements	3 Months Ended
	Mar. 31, 2015
Accounting Pronouncements [Abstract]
Accounting Pronouncements	2	Accounting Pronouncements
	Accounting Pronouncements Not Yet Adopted
	In May 2014, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2014-09, Revenue from Contracts with Customers. The amendment is effective retrospectively for fiscal years (and interim reporting periods within those years) beginning after December 15, 2017. Management is currently evaluating the impact that the adoption of this standard will have on our consolidated financial statements.
	In June 2014, the FASB issued ASU 2014-12, Accounting for Share-Based Payments When the Terms of an Award Provide That a Performance Target Could Be Achieved After the Requisite Service Period. The amendment is effective prospectively or retrospectively for fiscal years (and interim periods within those years) beginning after December 15, 2015 and is not expected to have a material impact on our financial condition or results of operations.
	In February 2015, the FASB issued ASU 2015-02, Consolidation – Amendments to the Consolidation Analysis. The amendment is effective retrospectively for fiscal years (and interim reporting periods within those years) beginning after December 15, 2015. Management is currently evaluating the impact that the adoption of this standard will have on our consolidated financial statements.
	In April 2015, the FASB issued ASU 2015-03, Simplifying the Presentation of Debt Issuance Costs, which requires debt issuance costs to be presented in the balance sheet as a direct deduction from the carrying value of the associated debt liability, consistent with the presentation of a debt discount. The amendment is effective retrospectively for fiscal years (and interim periods within those years) beginning after December 15, 2015 and is not expected to have a material impact on our financial condition or results of operations.

Longterm_Incentive_Compensatio

Long-term Incentive Compensation Plans	3 Months Ended
	Mar. 31, 2015
Long-term Incentive Compensation Plans [Abstract]
Long-term Incentive Compensation Plans	3	Long-term Incentive Compensation Plans
	We maintain several unfunded, non-qualified long-term incentive compensation plans, under which we grant annual awards to employees, generally in the fourth quarter.
	Awards granted in December 2014 and 2013 allowed participants to allocate their awards between restricted AB Holding Units and deferred cash. Participants (except certain members of senior management) generally could allocate up to 50% of their awards to deferred cash, not to exceed a total of $250,000 per award. Each of our employees based outside of the United States (other than expatriates) who received a 2014 or 2013 award of $100,000 or less could have allocated up to 100% of his or her award to deferred cash. For awards granted in 2014 and 2013, participants allocated their awards prior to the date on which the Compensation Committee granted awards, December 12, 2014 and 2013, respectively. These awards were valued using the closing price of an AB Holding Unit on these days. For awards granted in 2014 and 2013:
		Ÿ	We engaged in open-market purchases of AB Holding Units, or purchased newly-issued AB Holding Units from AB Holding, that were awarded to participants and held them in a consolidated rabbi trust.
		Ÿ	Quarterly distributions on vested and unvested AB Holding Units are paid currently to participants, regardless of whether or not a long-term deferral election has been made.
		Ÿ	Interest on deferred cash is accrued monthly based on our monthly weighted average cost of funds.
	We recognize compensation expense related to equity compensation grants in the financial statements using the fair value method. Fair value of restricted AB Holding Unit awards is the closing price of an AB Holding Unit on the grant date; fair value of options is determined using the Black-Scholes option valuation model. Under the fair value method, compensatory expense is measured at the grant date based on the estimated fair value of the award and is recognized over the required service period. For year-end long-term incentive compensation awards, employees who resign or are terminated without cause may retain their awards, subject to compliance with certain agreements and restrictive covenants set forth in the applicable award agreement, including restrictions on competition and employee and client solicitation, and a claw-back for failing to follow existing risk management policies. Due to there being no service requirement, we fully expense these awards on grant date. Most equity replacement, sign-on or similar deferred compensation awards included in separate employment agreements or arrangements include a required service period. Regardless of whether or not the award agreement includes employee service requirements, AB Holding Units typically are distributed to employees ratably over four years, unless a long-term deferral election has been made.
	Grants of restricted AB Holding Units and options to buy AB Holding Units typically are awarded during the second quarter to members of the Board of Directors (“Eligible Directors”) of the General Partner who are not employed by our company or by any of our affiliates. Restricted AB Holding Units are distributed on the third anniversary of the grant date and the options become exercisable ratably over three years. These restricted AB Holding Units and options are not forfeitable (except if the Eligible Director is terminated for “Cause”, as that term is defined in the applicable award agreement). Due to there being no service requirement, we fully expense these awards on grant date.
	We fund our restricted AB Holding Unit awards either by purchasing AB Holding Units on the open market or purchasing newly-issued AB Holding Units from AB Holding, all of which are then held in a consolidated rabbi trust until they are distributed to employees or retired. In accordance with the Amended and Restated Agreement of Limited Partnership of AB (“AB Partnership Agreement”), when AB purchases newly-issued AB Holding Units from AB Holding, AB Holding is required to use the proceeds it receives from AB to purchase the equivalent number of newly-issued AB Units, thus increasing its percentage ownership interest in AB. AB Holding Units held in the consolidated rabbi trust are corporate assets in the name of the trust and are available to the general creditors of AB.
	During the first quarter of 2015, we purchased 0.7 million AB Holding Units for $17.0 million (on a trade date basis). These amounts reflect open-market purchases of 0.6 million AB Holding Units for $15.1 million, with the remainder relating to purchases of AB Holding Units from employees to allow them to fulfill statutory tax withholding requirements at the time of distribution of long-term incentive compensation awards. During the first quarter of 2014, we purchased 0.2 million AB Holding Units for $3.7 million (on a trade date basis) from employees to allow them to fulfill statutory tax withholding requirements at the time of distribution of long-term incentive compensation awards.
	Each quarter, we implement plans to repurchase AB Holding Units pursuant to Rule 10b5-1 under the Securities Exchange Act of 1934, as amended (“Exchange Act”). A Rule 10b5-1 plan allows a company to repurchase its shares at times when it otherwise might be prevented from doing so because of self-imposed trading blackout periods or because it possesses material non-public information. Each broker we select has the authority under the terms and limitations specified in the plan to repurchase AB Holding Units on our behalf in accordance with the terms of the plan. Repurchases are subject to regulations promulgated by the SEC as well as certain price, market volume and timing constraints specified in the plan. The plan adopted during the first quarter of 2015 expired at the close of business on April 29, 2015. We may adopt additional Rule 10b5-1 plans in the future to engage in open-market purchases of AB Holding Units to help fund anticipated obligations under our incentive compensation award program and for other corporate purposes.
	During the first quarter of 2015 and 2014, we granted to employees and Eligible Directors 0.1 million and 0.2 million restricted AB Holding Unit awards, respectively. We used AB Holding Units repurchased during the period and newly-issued AB Holding Units to fund restricted AB Holding Unit awards.
	During the first quarter of 2015, AB Holding issued 0.2 million AB Holding Units upon exercise of options to buy AB Holding Units. AB Holding used the proceeds of $3.9 million received from employees as payment in cash for the exercise price to purchase the equivalent number of newly-issued AB Units.

Cash_Distributions

Cash Distributions	3 Months Ended
	Mar. 31, 2015
Cash Distributions [Abstract]
Cash Distributions	4	Cash Distributions
	AB is required to distribute all of its Available Cash Flow, as defined in the AB Partnership Agreement, to its Unitholders and to the General Partner. Available Cash Flow can be summarized as the cash flow received by AB from operations minus such amounts as the General Partner determines, in its sole discretion, should be retained by AB for use in its business, or plus such amounts as the General Partner determines, in its sole discretion, should be released from previously retained cash flow.
	Typically, Available Cash Flow has been the adjusted diluted net income per unit for the quarter multiplied by the number of general and limited partnership interests at the end of the quarter. In future periods, management anticipates that Available Cash Flow will be based on adjusted diluted net income per unit, unless management determines that one or more non-GAAP adjustments that are made for adjusted net income should not be made with respect to the Available Cash Flow calculation.
	On April 30, 2015, the General Partner declared a distribution of $0.51 per AB Unit, representing a distribution of Available Cash Flow for the three months ended March 31, 2015. The General Partner, as a result of its 1% general partnership interest, is entitled to receive 1% of each distribution. The distribution is payable on May 21, 2015 to holders of record on May 11, 2015.

Real_Estate_Charges

Real Estate Charges	3 Months Ended
	Mar. 31, 2015
Real Estate Charges [Abstract]
Real Estate Charges	5	Real Estate Charges
	During 2010, we performed a comprehensive review of our real estate requirements in New York in connection with our workforce reductions commencing in 2008. As a result, during 2010 we decided to sub-lease over 380,000 square feet in New York (all of this space has been sublet) and consolidate our New York-based employees into two office locations from three. During the third quarter of 2012, in an effort to further reduce our global real estate footprint, we completed a comprehensive review of our worldwide office locations and began implementing a global space consolidation plan. As a result, our intention is to sub-lease approximately 510,000 square feet of office space (approximately 90% of this space has been sublet), more than 70% of which is New York office space (in addition to the 380,000 square foot space reduction in 2010), with the remainder consisting of office space in England, Australia and various U.S. locations.
	During the first quarter of 2015, we recorded pre-tax real estate credits of $0.4 million, resulting from a change in estimates related to previously recorded real estate charges.
	The activity in the liability account relating to our 2010 and 2012 office space consolidation initiatives for the following periods is as follows:
			Three Months			Twelve Months
			Ended			Ended
			31-Mar-15			31-Dec-14
			(in thousands)
	Balance as of beginning of period		$	148,429		$	199,527
	Expense (credit) incurred			139			(4,755	)
	Deferred rent			—			—
	Payments made			(11,562	)		(50,893	)
	Interest accretion			1,082			4,550
	Balance as of end of period		$	138,088		$	148,429

Net_Income_per_Unit

Net Income per Unit	3 Months Ended
	Mar. 31, 2015
Net Income per Unit [Abstract]
Net Income per Unit	6	Net Income per Unit
	Basic net income per unit is derived by reducing net income for the 1% general partnership interest and dividing the remaining 99% by the basic weighted average number of units outstanding for each period. Diluted net income per unit is derived by reducing net income for the 1% general partnership interest and dividing the remaining 99% by the total of the diluted weighted average number of units outstanding for each period.
		Three Months Ended March 31,
		2015			2014
		(in thousands, except per unit amounts)
	Net income attributable to AB Unitholders		$	141,469		$	116,725
	Weighted average units outstanding – basic			272,831			268,459
	Dilutive effect of compensatory options to buy AB Holding Units			1,098			1,077
	Weighted average units outstanding – diluted			273,929			269,536
	Basic net income per AB Unit		$	0.51		$	0.43
	Diluted net income per AB Unit		$	0.51		$	0.43
	As of March 31, 2015 and 2014, we excluded 2,774,117 and 2,828,033 options, respectively, from the diluted net income per unit computation due to their anti-dilutive effect.

Cash_and_Securities_Segregated

Cash and Securities Segregated Under Federal Regulations and Other Requirements	3 Months Ended
	Mar. 31, 2015
Cash and Securities Segregated Under Federal Regulations and Other Requirements [Abstract]
Cash and Securities Segregated Under Federal Regulations and Other Requirements	7	Cash and Securities Segregated Under Federal Regulations and Other Requirements
	As of March 31, 2015 and December 31, 2014, $0.5 billion and $0.4 billion, respectively, of U.S. Treasury Bills were segregated in a special reserve bank custody account for the exclusive benefit of brokerage customers of Sanford C. Bernstein & Co., LLC (one of our subsidiaries, “SCB LLC”) under Rule 15c3-3 of the Exchange Act.
	AllianceBernstein Investments, Inc. (one of our subsidiaries, “AllianceBernstein Investments”), the distributor of company-sponsored U.S. mutual funds, maintains several special bank accounts for the exclusive benefit of customers. As of March 31, 2015 and December 31, 2014, $50.2 million and $61.3 million, respectively, of cash was segregated in these bank accounts.

Investments

Investments	3 Months Ended
	Mar. 31, 2015
Investments [Abstract]
Investments	8	Investments
	Investments consist of:
			31-Mar-15		31-Dec-14
			(in thousands)
	Available-for-sale (primarily seed capital)		$	6,442	$	6,172
	Trading:
	Long-term incentive compensation-related			60,594		74,095
	U.S. Treasury Bills			28,995		28,982
	Seed capital			425,805		400,746
	Equities			59,508		79,720
	Exchange-traded options			6,767		22,290
	Investments in limited partnership hedge funds:
	Long-term incentive compensation-related			19,952		24,684
	Seed capital			26,366		33,951
	Consolidated private equity fund (10% seed capital)			34,130		32,604
	Private equity (seed capital)			48,724		48,734
	Other			11,468		11,497
	Total investments		$	728,751	$	763,475
	Total investments related to long-term incentive compensation obligations of $80.5 million and $98.8 million as of March 31, 2015 and December 31, 2014, respectively, consist of company-sponsored mutual funds and hedge funds. For long-term incentive compensation awards granted before 2009, we typically made investments in our services that were notionally elected by plan participants and maintained them (and continue to maintain them) in a consolidated rabbi trust or separate custodial account. The rabbi trust and custodial account enable us to hold such investments separate from our other assets for the purpose of settling our obligations to participants. The investments held in the rabbi trust and custodial account remain available to the general creditors of AB.
	The underlying investments of the hedge funds in which we invest include long and short positions in equity securities, fixed income securities (including various agency and non-agency asset-based securities), currencies, commodities and derivatives (including various swaps and forward contracts). These investments are valued at quoted market prices or, where quoted market prices are not available, are fair valued based on the pricing policies and procedures of the underlying funds.
	U.S. Treasury Bills are held by SCB LLC in its investment account, the majority of which are pledged as collateral with clearing organizations. These clearing organizations have the ability by contract or custom to sell or re-pledge this collateral.
	We provide seed capital to our investment teams to develop new products and services for our clients. The seed capital trading investments are equity and fixed income products, primarily in the form of separately-managed account portfolios, U.S. mutual funds, Luxembourg funds, Japanese investment trust management funds or Delaware business trusts. Seed capital also includes investments in private equity funds, such as our consolidated venture capital fund, which holds technology, media, telecommunications, healthcare and clean-tech investments, and a third-party venture capital fund that invests in communications, consumer, digital media, healthcare and information technology markets.
	Trading securities also include long positions in corporate equities, an exchange-traded fund and long exchange-traded options traded through our options desk.
	The portion of trading gains (losses) for the three months ended March 31, 2015 and 2014 related to trading securities held as of March 31, 2015 and 2014 is as follows (in thousands):
			Three Months Ended March 31,
			2015		2014
			(in thousands)
	Net gains recognized during the period		$	6,784	$	14,812
	Less: net gains recognized during the period on trading securities sold during the period			6,047		4,404
	Unrealized gains recognized during the period on trading securities held		$	737	$	10,408

Derivative_Instruments

Derivative Instruments	3 Months Ended
	Mar. 31, 2015
Derivative Instruments [Abstract]
Derivative Instruments	9	Derivative Instruments
	We enter into various futures, forwards and swaps to economically hedge certain seed money investments.  Also, we have currency forwards that economically hedge certain cash accounts and exchange-traded futures to economically hedge a foreign investment. In addition, our options desk trades long and short exchange-traded equity options. We do not hold any derivatives designated in a formal hedge relationship under Accounting Standards Codification (“ASC”) 815-10, Derivatives and Hedging.
	The notional value and fair value as of March 31, 2015 and December 31, 2014 for derivative instruments (excluding our options desk trading activities) not designated as hedging instruments were as follows:
						Fair Value
			Notional Value			Asset Derivatives			Liability Derivatives
			(in thousands)
	March 31, 2015:
	Exchange-traded futures		$	143,141		$	360		$	3,011
	Currency forwards			204,894			1,948			963
	Interest rate swaps			59,126			1,909			3,045
	Credit default swaps			165,028			3,881			293
	Option swaps			11			11			—
	Total return swaps			102,096			442			2,461
	Total derivatives		$	674,296		$	8,551		$	9,773
	December 31, 2014:
	Exchange-traded futures		$	149,863		$	571		$	2,438
	Currency forwards			149,282			1,782			333
	Interest rate swaps			50,591			1,507			2,679
	Credit default swaps			32,745			1,432			110
	Option swaps			11			107			88
	Total return swaps			125,913			1,388			3,744
	Total derivatives		$	508,405		$	6,787		$	9,392
	As of March 31, 2015 and December 31, 2014, the derivative assets and liabilities are included in both receivables and payables to brokers and dealers on our condensed consolidated statements of financial condition.
	The gains and losses for derivative instruments (excluding our options desk trading activities) for the three months ended March 31, 2015 and 2014 recognized in investment gains (losses) in the condensed consolidated statements of income were as follows:
			Three Months Ended March 31,
			2015			2014
			(in thousands)
	Exchange-traded futures		$	(4,987	)	$	(498	)
	Currency forwards			3,452			(1,666	)
	Interest rate swaps			(745	)		(793	)
	Credit default swaps			(57	)		(5	)
	Options swaps			(17	)		(35	)
	Total return swaps			(3,701	)		(2,524	)
	Net (losses) on derivative instruments		$	(6,055	)	$	(5,521	)
	We may be exposed to credit-related losses in the event of nonperformance by counterparties to derivative financial instruments. We take steps to minimize our counterparty exposure through a credit review and approval process. In addition, we executed various collateral arrangements with counterparties to the over-the-counter derivative transactions that require both pledging and accepting collateral in the form of cash. As of March 31, 2015 and December 31, 2014, we held $1.1 million and $1.0 million, respectively, of cash collateral payable to trade counterparties. This obligation to return cash is reported in payables to brokers and dealers in our condensed consolidated statements of financial condition.
	Although notional amount is the most commonly used measure of volume in the derivative market, it is not used as a measure of credit risk. Generally, the current credit exposure of our derivative contracts is limited to the net positive estimated fair value of derivative contracts at the reporting date after taking into consideration the existence of netting agreements and any collateral received. A derivative with positive value (a derivative asset) indicates existence of credit risk because the counterparty would owe us if the contract were closed. Alternatively, a derivative contract with negative value (a derivative liability) indicates we would owe money to the counterparty if the contract were closed. Generally, if there is more than one derivative transaction with a single counterparty, a master netting arrangement exists with respect to derivative transactions with that counterparty to provide for aggregate net settlement.
	Certain of our standardized contracts for over-the-counter derivative transactions (“ISDA Master Agreements”) contain credit risk related contingent provisions related to each counterparty’s credit rating. In some ISDA Master Agreements, if the counterparty’s credit rating (or in some agreements, our AUM) falls below a specified threshold, either a default or a termination event permitting the counterparty to terminate the ISDA Master Agreement would be triggered. In all agreements that provide for collateralization, various levels of collateralization of net liability positions are applicable, depending on the credit rating of the counterparty. As of March 31, 2015 and December 31, 2014, we delivered $11.9 million and $13.2 million, respectively, of cash collateral into brokerage accounts. We report this cash collateral in cash and cash equivalents in our condensed consolidated statements of financial condition.
	As of March 31, 2015 and December 31, 2014, we held $6.8 million and $22.3 million, respectively, of long exchange-traded equity options, which are classified as trading investments and included in other investments on our condensed consolidated statements of financial condition. In addition, as of March 31, 2015 and December 31, 2014, we held $5.6 million and $7.1 million, respectively, of short exchange-traded equity options which are included in securities sold not yet purchased on our condensed consolidated statements of financial condition. Our options desk provides our clients with equity derivative strategies and execution for exchange-traded options on single stocks, exchange-traded funds and indices. While predominately agency-based, the options desk may commit capital to facilitate a client’s transaction. Our options desk hedges the risks associated with this activity by taking offsetting positions in equities. During the first quarter of 2015 and 2014, we recognized $32.8 million and $60.8 million, respectively, of losses on equity options activity. These losses are recognized in investment gains (losses) in the condensed consolidated statements of income.

Offsetting_Assets_and_Liabilit

Offsetting Assets and Liabilities	3 Months Ended
	Mar. 31, 2015
Offsetting Assets and Liabilities [Abstract]
Offsetting Assets and Liabilities	10	Offsetting Assets and Liabilities
	Offsetting of assets as of March 31, 2015 and December 31, 2014 was as follows:
			Gross Amounts of Recognized Assets		Gross Amounts Offset in the Statement of Financial Position		Net Amounts of Assets Presented in the Statement of Financial Position		Financial		Cash			Net
									Instruments		Collateral			Amount
											Received
			(in thousands)
	March 31, 2015:
	Securities borrowed		$	157,916	$	—	$	157,916	$	—	$	(157,916	)	$	—
	Derivatives		$	8,551	$	—	$	8,551	$	—	$	(1,078	)	$	7,473
	Long exchange- traded options		$	6,767	$	—	$	6,767	$	—	$	—		$	6,767
	December 31, 2014:
	Securities borrowed		$	158,147	$	—	$	158,147	$	—	$	(158,147	)	$	—
	Derivatives		$	6,787	$	—	$	6,787	$	—	$	(990	)	$	5,797
	Long exchange- traded options		$	22,290	$	—	$	22,290	$	—	$	—		$	22,290
	Offsetting of liabilities as of March 31, 2015 and December 31, 2014 was as follows:
			Gross Amounts of Recognized Liabilities		Gross Amounts Offset in the Statement of Financial Position		Net Amounts of Liabilities Presented in the Statement of Financial Position		Financial		Cash			Net Amount
									Instruments		Collateral
											Pledged
			(in thousands)
	March 31, 2015:
	Securities loaned		$	2,184	$	—	$	2,184	$	—	$	(2,184	)	$	—
	Derivatives		$	9,773	$	—	$	9,773	$	—	$	(9,773	)	$	—
	Short exchange-traded options		$	5,602	$	—	$	5,602	$	—	$	—		$	5,602
	December 31, 2014:
	Securities loaned		$	33,645	$	—	$	33,645	$	—	$	(33,645	)	$	—
	Derivatives		$	9,392	$	—	$	9,392	$	—	$	(9,392	)	$	—
	Short exchange-traded options		$	7,118	$	—	$	7,118	$	—	$	—		$	7,118
	Cash collateral pledged and received on derivative instruments are not considered material and are not disclosed by counterparty.

Fair_Value

Fair Value	3 Months Ended
	Mar. 31, 2015
Fair Value [Abstract]
Fair Value	11	Fair Value
	Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability (i.e., the “exit price”) in an orderly transaction between market participants at the measurement date. The three broad levels of fair value hierarchy are as follows:
		•	Level 1 – Quoted prices in active markets are available for identical assets or liabilities as of the reported date.
		•	Level 2 – Quoted prices in markets that are not active or other pricing inputs that are either directly or indirectly  observable as of the reported date.
		•	Level 3 –  Prices or valuation techniques that are both significant to the fair value measurement and  unobservable as of the reported date. These financial instruments do not have two-way markets and are  measured using management’s best estimate of fair value, where the inputs into the determination of fair value require significant management judgment or estimation.
	Assets and Liabilities Measured at Fair Value on a Recurring Basis
	Valuation of our financial instruments by pricing observability levels as of March 31, 2015 and December 31, 2014 was as follows (in thousands):
			Level 1				Level 2				Level 3		Total
	March 31, 2015:
	Money markets		$	172,415			$	—			$	—	$	172,415
	U.S. Treasury Bills			—				499,059				—		499,059
	Available-for-sale
	Equity securities			6,136				—				—		6,136
	Fixed income securities			306				—				—		306
	Trading
	Equity securities			334,792				24,680				122		359,594
	Fixed income securities			183,227				3,086				—		186,313
	Long exchange-traded options			6,767				—				—		6,767
	Derivatives			360				8,191				—		8,551
	Private equity			13,885				—				58,719		72,604
	Total assets measured at fair value		$	717,888			$	535,016			$	58,841	$	1,311,745
	Securities sold not yet purchased
	Short equities – corporate		$	61,302			$	—			$	—	$	61,302
	Short exchange-traded options			5,602				—				—		5,602
	Derivatives			3,011				6,762				—		9,773
	Contingent payment arrangements			—				—				42,223		42,223
	Total liabilities measured at fair value		$	69,915			$	6,762			$	42,223	$	118,900
	December 31, 2014:
	Money markets		$	89,566			$	—			$	—	$	89,566
	U.S. Treasury Bills			—				444,152				—		444,152
	Available-for-sale
	Equity securities			5,951				—				—		5,951
	Fixed income securities			221				—				—		221
	Trading
	Equity securities			387,495				7				—		387,502
	Fixed income securities			164,317				2,742				—		167,059
	Long exchange-traded options			22,290				—				—		22,290
	Derivatives			571				6,216				—		6,787
	Private equity			12,162				—				58,926		71,088
	Total assets measured at fair value		$	682,573			$	453,117			$	58,926	$	1,194,616
	Securities sold not yet purchased
	Short equities – corporate		$	81,784			$	—			$	—	$	81,784
	Short exchange-traded options			7,118				—				—		7,118
	Derivatives			2,438				6,954				—		9,392
	Contingent payment arrangements			—				—				42,436		42,436
	Total liabilities measured at fair value		$	91,340			$	6,954			$	42,436	$	140,730
	We provide below a description of the fair value methodologies used for instruments measured at fair value, as well as the general classification of such instruments pursuant to the valuation hierarchy:
		•	Money markets: We invest excess cash in various money market funds that are valued based on quoted prices in active markets; these are included in Level 1 of the valuation hierarchy.
		•	Treasury Bills: We hold U.S. Treasury Bills, which are primarily segregated in a special reserve bank custody account as required by Rule 15c3-3 of the Exchange Act. These securities are valued based on quoted yields in secondary markets and are included in Level 2 of the valuation hierarchy.
		•	Equity and fixed income securities: Our equity and fixed income securities consist principally of company-sponsored mutual funds with net asset values and various separately-managed portfolios consisting primarily of equity and fixed income securities with quoted prices in active markets, which are included in Level 1 of the valuation hierarchy. In addition, some securities are valued based on observable inputs from recognized pricing vendors, which are included in Level 2 of the valuation hierarchy.
		•	Derivatives: We hold exchange-traded futures with counterparties that are included in Level 1 of the valuation hierarchy. In addition, we also hold currency forward contracts, interest rate swaps, credit default swaps, option swaps and total return swaps with counterparties that are included in Level 2 of the valuation hierarchy.
		•	Options: We hold long exchange-traded options that are included in Level 1 of the valuation hierarchy.
		•	Private equity: Generally, the valuation of private equity investments owned by our consolidated venture capital fund or by us directly (regarding an investment in a private equity fund focused exclusively on the energy sector) requires significant management judgment due to the absence of quoted market prices, inherent lack of liquidity and the long-term nature of such investments. Private equity investments are valued initially at cost. The carrying values of private equity investments are adjusted either up or down from cost to reflect expected exit values as evidenced by financing and sale transactions with third parties, or when determination of a valuation adjustment is confirmed through ongoing review in accordance with our valuation policies and procedures. A variety of factors are reviewed and monitored to assess positive and negative changes in valuation, including current operating performance and future expectations of investee companies, industry valuations of comparable public companies, changes in market outlooks, and the third party financing environment over time. In determining valuation adjustments resulting from the investment review process, particular emphasis is placed on current company performance and market conditions. For these reasons, which make the fair value of private equity investments unobservable, equity investments are included in Level 3 of the valuation hierarchy. We also invest in a third-party venture capital fund in which fair value is based on our capital account balance provided by the partnership and is included in Level 3 of the valuation hierarchy. If private equity investments owned by our consolidated venture capital fund become publicly-traded, they are included in Level 1 of the valuation hierarchy. Also, if they contain trading restrictions, publicly-traded equity investments are included in Level 2 of the valuation hierarchy. During the first quarter of 2015, $26,000 was transferred from a Level 3 classification to a Level 1 classification.
		•	Securities sold not yet purchased: Securities sold not yet purchased, primarily reflecting short positions in equities and exchange-traded options, are included in Level 1 of the valuation hierarchy.
		•	Contingent payment arrangements: Contingent payment arrangements relate to contingent payment liabilities associated with acquisitions in 2010, 2013 and 2014. At each reporting date, we estimate the fair values of the contingent consideration expected to be paid based upon probability-weighted AUM and revenue projections, using unobservable market data inputs, which are included in Level 3 of the valuation hierarchy.
	The change in carrying value associated with private equity and trading equity securities Level 3 financial instruments carried at fair value is as follows:
			Three Months Ended March 31,
			2015				2014
			(in thousands)
	Balance as of beginning of period		$	58,926			$	52,081
	Transfer out			(26	)			—
	Purchases			122				501
	Sales			—				(1,121	)
	Realized (losses) gains, net			(5,194	)			1,121
Unrealized gains (losses), net			5,013				(1,838	)
Balance as of end of period		$	58,841			$	50,744
Transfers into and out of all levels of the fair value hierarchy are reflected at end-of-period fair values. Realized and unrealized gains and losses on Level 3 financial instruments are recorded in investment gains and losses in the condensed consolidated statements of income. Approximately one-third of the Level 3 investments are private equity investments owned by our consolidated venture capital fund, of which we own 10% and non-controlling interests own 90%.
Quantitative information about private equity Level 3 fair value measurements as of March 31, 2015 and December 31, 2014 is as follows:
		Fair Value as			Valuation Technique		Unobservable Input		Range
		of March 31,
		2015
		(in thousands)
Private Equity:
Technology, Media and Telecommunications		$	20,044		Market comparable companies		Revenue multiple			2.1 – 4.6
							Marketability discount			30	%
In addition, as of March 31, 2015, there are two investments (with a combined fair value of $0.1 million) in the Healthcare and Clean-tech category that are classified as Level 3. The first investment is valued based on liquidation value and the second investment is a warrant valued using the Black-Scholes option valuation model. Also, we have an investment in a private equity fund focused exclusively on the energy sector (fair value of $7.5 million) that is classified as Level 3. This investment’s valuation is based on a market approach, considering recent transactions of the fund and the industry.
		Fair Value as			Valuation Technique		Unobservable Input		Range
		of December 31,
		2014
		(in thousands)
Private Equity:
Technology, Media and Telecommunications		$	20,112		Market comparable companies		Revenue multiple			2.0 – 3.5
							Discount rate			18	%
							Discount years		2.0 years
In addition, as of December 31, 2014, there are two investments (with a combined fair value of $0.2 million) in the Healthcare and Clean-tech category that are classified as Level 3. The first investment is valued based on liquidation value and the second investment is a warrant valued using the Black-Scholes option valuation model. Also, we have an investment in a private equity fund focused exclusively on the energy sector (fair value of $7.5 million) that is classified as Level 3. This investment’s valuation is based on a market approach, considering recent transactions of the fund and the industry.
The significant unobservable inputs used in the fair value measurement of the reporting entities’ venture capital securities in the Technology, Media and Telecommunications areas are enterprise value to revenue multiples and a discount to account for liquidity and various risk factors. Significant increases (decreases) in the enterprise value to revenue multiple inputs in isolation would result in a significantly higher (lower) fair value measurement. Significant increases (decreases) in the discount would result in a significantly lower (higher) fair value measurement.
One of our private equity investments is a venture capital fund (fair value of $31.0 million and unfunded commitment of $2.9 million as of March 31, 2015) that invests in communications, consumer, digital media, healthcare and information technology markets. In addition, one of the investments included in our consolidated private equity fund (fair value of $0.1 million and no unfunded commitment as of March 31, 2015) is a venture capital fund investing in clean energy, resource and energy efficiency and other sustainable industries. The fair value of each of these investments has been estimated using the capital account balances provided by the partnerships. The interests in these partnerships cannot be redeemed.
The change in carrying value associated with contingent payment arrangements Level 3 financial instruments carried at fair value is as follows:
		Three Months Ended March 31,
		2015				2014
	(in thousands)
Balance as of beginning of period		$	42,436			$	38,205
Accretion			443				321
Payments			(656	)			(838	)
Balance as of end of period		$	42,223			$	37,688
Quantitative information about contingent payment arrangements Level 3 fair value measurements as of March 31, 2015 and December 31, 2014 is as follows:
Our three acquisition-related contingent consideration liabilities (with a combined fair value of $42.2 million as of March 31, 2015 and $42.4 million as of December 31, 2014) are currently valued using projected AUM growth rates with a weighted average of 46%, revenue growth rates with a weighted average of 71%, and discount rates ranging between 3% (when using a cost of debt assumption) and 18% (when using a cost of capital assumption).
Assets and Liabilities Measured at Fair Value on a Nonrecurring Basis
We did not have any material assets or liabilities that were measured at fair value for impairment on a nonrecurring basis during the three months ended March 31, 2015 or during the year ended December 31, 2014.

Commitments_and_Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2015
Commitments and Contingencies [Abstract]
Commitments and Contingencies	12	Commitments and Contingencies
	Legal Proceedings
	With respect to all significant litigation matters, we consider the likelihood of a negative outcome.  If we determine the likelihood of a negative outcome is probable and the amount of the loss can be reasonably estimated, we record an estimated loss for the expected outcome of the litigation. If the likelihood of a negative outcome is reasonably possible and we are able to determine an estimate of the possible loss or range of loss in excess of amounts already accrued, if any, we disclose that fact together with the estimate of the possible loss or range of loss. However, it is often difficult to predict the outcome or estimate a possible loss or range of loss because litigation is subject to inherent uncertainties, particularly when plaintiffs allege substantial or indeterminate damages. Such is also the case when the litigation is in its early stages or when the litigation is highly complex or broad in scope. In these cases, we disclose that we are unable to predict the outcome or estimate a possible loss or range of loss.
	During the first quarter of 2012, we received a legal letter of claim (“Letter of Claim”) sent on behalf of Philips Pension Trustees Limited and Philips Electronics U.K. Limited (“Philips”), a former pension fund client, alleging that AllianceBernstein Limited (one of our subsidiaries organized in the U.K.) was negligent and failed to meet certain applicable standards of care with respect to the initial investment in, and management of, a £500 million portfolio of U.S. mortgage-backed securities. The alleged damages range between $177 million and $234 million, plus compound interest on an alleged $125 million of realized losses in the portfolio. On January 2, 2014, Philips filed a claim form (“Claim”) in the High Court of Justice in London, England, which formally commenced litigation with respect to the allegations in the Letter of Claim.
	We believe that any losses to Philips resulted from adverse developments in the U.S. housing and mortgage market that precipitated the financial crisis in 2008 and not from any negligence or failure on our part. We believe that we have strong defenses to these claims, which are set forth in our October 12, 2012 response to the Letter of Claim and our June 27, 2014 Statement of Defence in response to the Claim, and will defend this matter vigorously. Currently, we are unable to estimate a reasonably possible range of loss because the matter remains in its early stages.
	In addition to the Claim discussed immediately above, we are involved in various other matters, including regulatory inquiries, administrative proceedings and litigation, some of which allege significant damages.
	In management’s opinion, an adequate accrual has been made as of March 31, 2015 to provide for any probable losses regarding any litigation matters for which we can reasonably estimate an amount of loss. It is reasonably possible that we could incur additional losses pertaining to these matters, but currently we cannot estimate any such additional losses.
	Management, after consultation with legal counsel, currently believes that the outcome of any matter that is pending or threatened, or all of them combined, will not have a material adverse effect on our results of operations, financial condition or liquidity. However, any inquiry, proceeding or litigation has an element of uncertainty; management cannot determine whether further developments relating to any matter that is pending or threatened, or all of them combined, will have a material adverse effect on our results of operation, financial condition or liquidity in any future reporting period.

Units_Outstanding

Units Outstanding	3 Months Ended
	Mar. 31, 2015
Units Outstanding [Abstract]
Units Outstanding	13	Units Outstanding
	Changes in limited partnership units outstanding during the three-month period ended March 31, 2015 were as follows:
	Outstanding as of December 31, 2014		273,040,452
	Options exercised		228,816
	Units issued		27,755
	Units retired		(689,430	)
	Outstanding as of March 31, 2015		272,607,593
	During the first quarter of 2015, we purchased 400 AB Units in private transactions and retired them.

Debt

Debt	3 Months Ended
	Mar. 31, 2015
Debt [Abstract]
Debt	14	Debt
	As of March 31, 2015 and December 31, 2014, AB had $500.6 million and $489.0 million, respectively, in commercial paper outstanding with weighted average interest rates of approximately 0.3% for both periods. The commercial paper is short term in nature, and as such, recorded value is estimated to approximate fair value (and considered a Level 2 security in the fair value hierarchy). Average daily borrowings of commercial paper during the first three months of 2015 and the full year 2014 were $423.9 million and $335.0 million, respectively, with weighted average interest rates of approximately 0.3% and 0.2%, respectively.

Changes_in_Capital

Changes in Capital	3 Months Ended
	Mar. 31, 2015
Changes in Capital [Abstract]
Changes in Capital	15	Changes in Capital
	Changes in capital during the three-month period ended March 31, 2015 were as follows:
			Partners’ Capital Attributable to AB Unitholders			Non-Controlling Interests In Consolidated Entities			Total Capital
			(in thousands)
	Balance as of  December 31, 2014		$	4,085,465		$	30,396		$	4,115,861
	Comprehensive income:
	Net income			141,469			1,275			142,744
	Other comprehensive income, net of tax:
	Unrealized gains on investments			308			—			308
	Foreign currency translation adjustments			(12,208	)		(67	)		(12,275	)
	Changes in employee benefit related items			175			—			175
	Comprehensive income			129,744			1,208			130,952
	Distributions to General Partner and unitholders			(173,075	)		—			(173,075	)
	Capital contributions from affiliates			6,354			—			6,354
	Compensation-related transactions			(9,642	)		—			(9,642	)
	Other			(11	)		203			192
	Balance as of March 31, 2015		$	4,038,835		$	31,807		$	4,070,642
	Changes in capital during the three-month period ended March 31, 2014 were as follows:
			Partners’ Capital Attributable to AB Unitholders			Non-Controlling Interests In Consolidated Entities			Total Capital
			(in thousands)
	Balance as of  December 31, 2013		$	4,027,486		$	42,240		$	4,069,726
	Comprehensive income:
	Net income			116,725			1,813			118,538
	Other comprehensive income, net of tax:
	Unrealized gains on investments			289			—			289
	Foreign currency translation adjustments			2,108			41			2,149
	Changes in employee benefit related items			(833	)		—			(833	)
	Comprehensive income			118,289			1,854			120,143
	Distributions to General Partner and unitholders			(178,994	)		—			(178,994	)
	Capital contributions from affiliates			6,209			—			6,209
	Purchases of AB Units			(229	)		—			(229	)
	Compensation-related transactions			7,398			—			7,398
	Balance as of March 31, 2014		$	3,980,159		$	44,094		$	4,024,253
	Deferred taxes are not recognized on foreign currency translation adjustments for foreign subsidiaries whose earnings are considered permanently invested outside the United States.

Acquisitions

Acquisitions	3 Months Ended
	Mar. 31, 2015
Acquisitions [Abstract]
Acquisitions	16	Acquisitions
	Acquisitions are accounted for under ASC 805, Business Combinations.
	On June 20, 2014, we acquired an approximate 82% ownership interest in CPH Capital Fondsmaeglerselskab A/S (“CPH”), a Danish asset management firm that managed approximately $3 billion in global core equity assets for institutional investors, for a cash payment of $64.4 million and a contingent consideration payable of $9.4 million. The excess of the purchase price over the fair value of identifiable assets acquired resulted in the recognition of $58.1 million of goodwill. We recorded $24.1 million of definite-lived intangible assets relating to separately-managed account relationships and $3.5 million of indefinite-lived intangible assets relating to an acquired fund’s investment contract. We also recorded redeemable non-controlling interest of $16.5 million relating to the fair value of the portion of CPH we do not own.

Business_Description_Organizat1

Business Description, Organization and Basis of Presentation (Policies)	3 Months Ended
	Mar. 31, 2015
Business Description, Organization and Basis of Presentation [Abstract]
Basis of Presentation	Basis of Presentation
	The interim condensed consolidated financial statements have been prepared in accordance with the instructions to Form 10-Q pursuant to the rules and regulations of the U.S. Securities and Exchange Commission (“SEC”). In the opinion of management, all adjustments, consisting only of normal recurring adjustments, necessary for a fair statement of the interim results, have been made. The preparation of the condensed consolidated financial statements requires management to make certain estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the dates of the condensed consolidated financial statements and the reported amounts of revenues and expenses during the interim reporting periods. Actual results could differ from those estimates. The December 31, 2014 condensed consolidated statement of financial condition was derived from audited financial statements but does not include all disclosures required by accounting principles generally accepted in the United States of America.
	The condensed consolidated financial statements include AB and its majority-owned and/or controlled subsidiaries. All significant inter-company transactions and balances among the consolidated entities have been eliminated.
Reclassifications	Reclassification
	The first quarter 2014 amounts for Institutional and Private Wealth Management finders’ fees previously presented as other promotion and servicing are now presented as distribution-related payments in the condensed consolidated statements of income to conform to the current year’s presentation.

Accounting_Pronouncements_Poli

Accounting Pronouncements (Policies)	3 Months Ended
	Mar. 31, 2015
Accounting Pronouncements [Abstract]
Accounting Pronouncements Not yet Adopted	Accounting Pronouncements Not Yet Adopted
	In May 2014, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2014-09, Revenue from Contracts with Customers. The amendment is effective retrospectively for fiscal years (and interim reporting periods within those years) beginning after December 15, 2017. Management is currently evaluating the impact that the adoption of this standard will have on our consolidated financial statements.
	In June 2014, the FASB issued ASU 2014-12, Accounting for Share-Based Payments When the Terms of an Award Provide That a Performance Target Could Be Achieved After the Requisite Service Period. The amendment is effective prospectively or retrospectively for fiscal years (and interim periods within those years) beginning after December 15, 2015 and is not expected to have a material impact on our financial condition or results of operations.
	In February 2015, the FASB issued ASU 2015-02, Consolidation – Amendments to the Consolidation Analysis. The amendment is effective retrospectively for fiscal years (and interim reporting periods within those years) beginning after December 15, 2015. Management is currently evaluating the impact that the adoption of this standard will have on our consolidated financial statements.
	In April 2015, the FASB issued ASU 2015-03, Simplifying the Presentation of Debt Issuance Costs, which requires debt issuance costs to be presented in the balance sheet as a direct deduction from the carrying value of the associated debt liability, consistent with the presentation of a debt discount. The amendment is effective retrospectively for fiscal years (and interim periods within those years) beginning after December 15, 2015 and is not expected to have a material impact on our financial condition or results of operations.

Business_Description_Organizat2

Business Description, Organization and Basis of Presentation (Tables)	3 Months Ended
	Mar. 31, 2015
Business Description, Organization and Basis of Presentation [Abstract]
Ownership interest by limited partners	As of March 31, 2015, the ownership structure of AB, expressed as a percentage of general and limited partnership interests, was as follows:
	AXA and its subsidiaries	62.2	%
	AB Holding	36.4
	Unaffiliated holders	1.4
		100	%

Real_Estate_Charges_Tables

Real Estate Charges (Tables)	3 Months Ended
	Mar. 31, 2015
Real Estate Charges [Abstract]
Real estate liability account activity related to office space consolidation initiatives	The activity in the liability account relating to our 2010 and 2012 office space consolidation initiatives for the following periods is as follows:
		Three Months			Twelve Months
		Ended			Ended
		31-Mar-15			31-Dec-14
		(in thousands)
	Balance as of beginning of period	$	148,429		$	199,527
	Expense (credit) incurred		139			(4,755	)
	Deferred rent		—			—
	Payments made		(11,562	)		(50,893	)
	Interest accretion		1,082			4,550
	Balance as of end of period	$	138,088		$	148,429

Net_Income_per_Unit_Tables

Net Income per Unit (Tables)	3 Months Ended
	Mar. 31, 2015
Net Income per Unit [Abstract]
Earnings per unit, basic and diluted	Basic net income per unit is derived by reducing net income for the 1% general partnership interest and dividing the remaining 99% by the basic weighted average number of units outstanding for each period. Diluted net income per unit is derived by reducing net income for the 1% general partnership interest and dividing the remaining 99% by the total of the diluted weighted average number of units outstanding for each period.
		Three Months Ended March 31,
		2015			2014
		(in thousands, except per unit amounts)
	Net income attributable to AB Unitholders		$	141,469		$	116,725
	Weighted average units outstanding – basic			272,831			268,459
	Dilutive effect of compensatory options to buy AB Holding Units			1,098			1,077
	Weighted average units outstanding – diluted			273,929			269,536
	Basic net income per AB Unit		$	0.51		$	0.43
	Diluted net income per AB Unit		$	0.51		$	0.43

Investments_Tables

Investments (Tables)	3 Months Ended
	Mar. 31, 2015
Investments [Abstract]
Investments	Investments consist of:
		31-Mar-15		31-Dec-14
		(in thousands)
	Available-for-sale (primarily seed capital)	$	6,442	$	6,172
	Trading:
	Long-term incentive compensation-related		60,594		74,095
	U.S. Treasury Bills		28,995		28,982
	Seed capital		425,805		400,746
	Equities		59,508		79,720
	Exchange-traded options		6,767		22,290
	Investments in limited partnership hedge funds:
	Long-term incentive compensation-related		19,952		24,684
	Seed capital		26,366		33,951
	Consolidated private equity fund (10% seed capital)		34,130		32,604
	Private equity (seed capital)		48,724		48,734
	Other		11,468		11,497
	Total investments	$	728,751	$	763,475
Portion of trading gains (losses) related to trading securities	The portion of trading gains (losses) for the three months ended March 31, 2015 and 2014 related to trading securities held as of March 31, 2015 and 2014 is as follows (in thousands):
		Three Months Ended March 31,
		2015		2014
		(in thousands)
	Net gains recognized during the period	$	6,784	$	14,812
	Less: net gains recognized during the period on trading securities sold during the period		6,047		4,404
	Unrealized gains recognized during the period on trading securities held	$	737	$	10,408

Derivative_Instruments_Tables

Derivative Instruments (Tables)	3 Months Ended
	Mar. 31, 2015
Derivative Instruments [Abstract]
Notional amount and fair value for derivative instruments not designated as hedging instruments	The notional value and fair value as of March 31, 2015 and December 31, 2014 for derivative instruments (excluding our options desk trading activities) not designated as hedging instruments were as follows:
					Fair Value
		Notional Value			Asset Derivatives			Liability Derivatives
		(in thousands)
	March 31, 2015:
	Exchange-traded futures	$	143,141		$	360		$	3,011
	Currency forwards		204,894			1,948			963
	Interest rate swaps		59,126			1,909			3,045
	Credit default swaps		165,028			3,881			293
	Option swaps		11			11			—
	Total return swaps		102,096			442			2,461
	Total derivatives	$	674,296		$	8,551		$	9,773
	December 31, 2014:
	Exchange-traded futures	$	149,863		$	571		$	2,438
	Currency forwards		149,282			1,782			333
	Interest rate swaps		50,591			1,507			2,679
	Credit default swaps		32,745			1,432			110
	Option swaps		11			107			88
	Total return swaps		125,913			1,388			3,744
	Total derivatives	$	508,405		$	6,787		$	9,392
Gains and losses recognized in investment gains (losses) in condensed consolidated statement of income	The gains and losses for derivative instruments (excluding our options desk trading activities) for the three months ended March 31, 2015 and 2014 recognized in investment gains (losses) in the condensed consolidated statements of income were as follows:
		Three Months Ended March 31,
		2015			2014
		(in thousands)
	Exchange-traded futures	$	(4,987	)	$	(498	)
	Currency forwards		3,452			(1,666	)
	Interest rate swaps		(745	)		(793	)
	Credit default swaps		(57	)		(5	)
	Options swaps		(17	)		(35	)
	Total return swaps		(3,701	)		(2,524	)
	Net (losses) on derivative instruments	$	(6,055	)	$	(5,521	)

Offsetting_Assets_and_Liabilit1

Offsetting Assets and Liabilities (Tables)	3 Months Ended
	Mar. 31, 2015
Offsetting Assets and Liabilities [Abstract]
Offsetting of financial assets	Offsetting of assets as of March 31, 2015 and December 31, 2014 was as follows:
		Gross Amounts of Recognized Assets		Gross Amounts Offset in the Statement of Financial Position		Net Amounts of Assets Presented in the Statement of Financial Position		Financial		Cash			Net
								Instruments		Collateral			Amount
										Received
		(in thousands)
	March 31, 2015:
	Securities borrowed	$	157,916	$	—	$	157,916	$	—	$	(157,916	)	$	—
	Derivatives	$	8,551	$	—	$	8,551	$	—	$	(1,078	)	$	7,473
	Long exchange- traded options	$	6,767	$	—	$	6,767	$	—	$	—		$	6,767
	December 31, 2014:
	Securities borrowed	$	158,147	$	—	$	158,147	$	—	$	(158,147	)	$	—
	Derivatives	$	6,787	$	—	$	6,787	$	—	$	(990	)	$	5,797
	Long exchange- traded options	$	22,290	$	—	$	22,290	$	—	$	—		$	22,290
Offsetting of financial liabilities	Offsetting of liabilities as of March 31, 2015 and December 31, 2014 was as follows:
		Gross Amounts of Recognized Liabilities		Gross Amounts Offset in the Statement of Financial Position		Net Amounts of Liabilities Presented in the Statement of Financial Position		Financial		Cash			Net Amount
								Instruments		Collateral
										Pledged
		(in thousands)
	March 31, 2015:
	Securities loaned	$	2,184	$	—	$	2,184	$	—	$	(2,184	)	$	—
	Derivatives	$	9,773	$	—	$	9,773	$	—	$	(9,773	)	$	—
	Short exchange-traded options	$	5,602	$	—	$	5,602	$	—	$	—		$	5,602
	December 31, 2014:
	Securities loaned	$	33,645	$	—	$	33,645	$	—	$	(33,645	)	$	—
	Derivatives	$	9,392	$	—	$	9,392	$	—	$	(9,392	)	$	—
	Short exchange-traded options	$	7,118	$	—	$	7,118	$	—	$	—		$	7,118

Fair_Value_Tables

Fair Value (Tables)	3 Months Ended
	Mar. 31, 2015
Fair Value [Abstract]
Fair value of assets and liabilities measured on a recurring basis	Valuation of our financial instruments by pricing observability levels as of March 31, 2015 and December 31, 2014 was as follows (in thousands):
			Level 1				Level 2				Level 3		Total
	March 31, 2015:
	Money markets		$	172,415			$	—			$	—	$	172,415
	U.S. Treasury Bills			—				499,059				—		499,059
	Available-for-sale
	Equity securities			6,136				—				—		6,136
	Fixed income securities			306				—				—		306
	Trading
	Equity securities			334,792				24,680				122		359,594
	Fixed income securities			183,227				3,086				—		186,313
	Long exchange-traded options			6,767				—				—		6,767
	Derivatives			360				8,191				—		8,551
	Private equity			13,885				—				58,719		72,604
	Total assets measured at fair value		$	717,888			$	535,016			$	58,841	$	1,311,745
	Securities sold not yet purchased
	Short equities – corporate		$	61,302			$	—			$	—	$	61,302
	Short exchange-traded options			5,602				—				—		5,602
	Derivatives			3,011				6,762				—		9,773
	Contingent payment arrangements			—				—				42,223		42,223
	Total liabilities measured at fair value		$	69,915			$	6,762			$	42,223	$	118,900
	December 31, 2014:
	Money markets		$	89,566			$	—			$	—	$	89,566
	U.S. Treasury Bills			—				444,152				—		444,152
	Available-for-sale
	Equity securities			5,951				—				—		5,951
	Fixed income securities			221				—				—		221
	Trading
	Equity securities			387,495				7				—		387,502
	Fixed income securities			164,317				2,742				—		167,059
	Long exchange-traded options			22,290				—				—		22,290
	Derivatives			571				6,216				—		6,787
	Private equity			12,162				—				58,926		71,088
	Total assets measured at fair value		$	682,573			$	453,117			$	58,926	$	1,194,616
	Securities sold not yet purchased
	Short equities – corporate		$	81,784			$	—			$	—	$	81,784
	Short exchange-traded options			7,118				—				—		7,118
	Derivatives			2,438				6,954				—		9,392
	Contingent payment arrangements			—				—				42,436		42,436
	Total liabilities measured at fair value		$	91,340			$	6,954			$	42,436	$	140,730
Fair value measurement Level 3 reconciliation	The change in carrying value associated with private equity and trading equity securities Level 3 financial instruments carried at fair value is as follows:
			Three Months Ended March 31,
			2015				2014
			(in thousands)
	Balance as of beginning of period		$	58,926			$	52,081
	Transfer out			(26	)			—
	Purchases			122				501
	Sales			—				(1,121	)
	Realized (losses) gains, net			(5,194	)			1,121
	Unrealized gains (losses), net			5,013				(1,838	)
	Balance as of end of period		$	58,841			$	50,744
Information about Level 3 fair value measurements	Quantitative information about private equity Level 3 fair value measurements as of March 31, 2015 and December 31, 2014 is as follows:
			Fair Value as			Valuation Technique		Unobservable Input		Range
			of March 31,
			2015
			(in thousands)
	Private Equity:
	Technology, Media and Telecommunications		$	20,044		Market comparable companies		Revenue multiple			2.1 – 4.6
								Marketability discount			30	%
	In addition, as of March 31, 2015, there are two investments (with a combined fair value of $0.1 million) in the Healthcare and Clean-tech category that are classified as Level 3. The first investment is valued based on liquidation value and the second investment is a warrant valued using the Black-Scholes option valuation model. Also, we have an investment in a private equity fund focused exclusively on the energy sector (fair value of $7.5 million) that is classified as Level 3. This investment’s valuation is based on a market approach, considering recent transactions of the fund and the industry.
			Fair Value as			Valuation Technique		Unobservable Input		Range
			of December 31,
			2014
			(in thousands)
	Private Equity:
	Technology, Media and Telecommunications		$	20,112		Market comparable companies		Revenue multiple			2.0 – 3.5
								Discount rate			18	%
								Discount years		2.0 years
Change in carrying value associated with contingent payment arrangements Level 3 financial instruments	The change in carrying value associated with contingent payment arrangements Level 3 financial instruments carried at fair value is as follows:
			Three Months Ended March 31,
			2015				2014
		(in thousands)
	Balance as of beginning of period		$	42,436			$	38,205
	Accretion			443				321
	Payments			(656	)			(838	)
	Balance as of end of period		$	42,223			$	37,688

Units_Outstanding_Tables

Units Outstanding (Tables)	3 Months Ended
	Mar. 31, 2015
Units Outstanding [Abstract]
Changes in units outstanding	Changes in limited partnership units outstanding during the three-month period ended March 31, 2015 were as follows:
	Outstanding as of December 31, 2014	273,040,452
	Options exercised	228,816
	Units issued	27,755
	Units retired	(689,430	)
	Outstanding as of March 31, 2015	272,607,593

Changes_in_Capital_Tables

Changes in Capital (Tables)	3 Months Ended
	Mar. 31, 2015
Changes in Capital [Abstract]
Changes in Capital	Changes in capital during the three-month period ended March 31, 2015 were as follows:
		Partners’ Capital Attributable to AB Unitholders			Non-Controlling Interests In Consolidated Entities			Total Capital
		(in thousands)
	Balance as of  December 31, 2014	$	4,085,465		$	30,396		$	4,115,861
	Comprehensive income:
	Net income		141,469			1,275			142,744
	Other comprehensive income, net of tax:
	Unrealized gains on investments		308			—			308
	Foreign currency translation adjustments		(12,208	)		(67	)		(12,275	)
	Changes in employee benefit related items		175			—			175
	Comprehensive income		129,744			1,208			130,952
	Distributions to General Partner and unitholders		(173,075	)		—			(173,075	)
	Capital contributions from affiliates		6,354			—			6,354
	Compensation-related transactions		(9,642	)		—			(9,642	)
	Other		(11	)		203			192
	Balance as of March 31, 2015	$	4,038,835		$	31,807		$	4,070,642
	Changes in capital during the three-month period ended March 31, 2014 were as follows:
		Partners’ Capital Attributable to AB Unitholders			Non-Controlling Interests In Consolidated Entities			Total Capital
		(in thousands)
	Balance as of  December 31, 2013	$	4,027,486		$	42,240		$	4,069,726
	Comprehensive income:
	Net income		116,725			1,813			118,538
	Other comprehensive income, net of tax:
	Unrealized gains on investments		289			—			289
	Foreign currency translation adjustments		2,108			41			2,149
	Changes in employee benefit related items		(833	)		—			(833	)
	Comprehensive income		118,289			1,854			120,143
	Distributions to General Partner and unitholders		(178,994	)		—			(178,994	)
	Capital contributions from affiliates		6,209			—			6,209
	Purchases of AB Units		(229	)		—			(229	)
	Compensation-related transactions		7,398			—			7,398
	Balance as of March 31, 2014	$	3,980,159		$	44,094		$	4,024,253

Business_Description_Organizat3

Business Description, Organization and Basis of Presentation (Details) (USD $)	0 Months Ended	3 Months Ended
In Millions, except Share data, unless otherwise specified	Apr. 30, 2015	Mar. 31, 2015
Ownership structure of AllianceBernstein expressed as a percentage of general and limited partnership interests [Abstract]
AXA and its subsidiaries ownership interest in holding company (in hundredths)		1.40%
Limited partners or members ownership interest in company (in hundredths)		100.00%
General partnership information [Abstract]
General Partnership number of general partnership units owned in Holding Company (in units)		100,000
General partnership interest in Company (in hundredths)	1.00%	1.00%
AXA and its subsidiaries economic interest in Company (in hundredths)		62.70%
Threshold amount for including institutions in private clients		$25
AXA and its Subsidiaries [Member]
Ownership structure of AllianceBernstein expressed as a percentage of general and limited partnership interests [Abstract]
Limited partners or members ownership interest in company (in hundredths)		62.20%
AB Holding [Member]
Ownership structure of AllianceBernstein expressed as a percentage of general and limited partnership interests [Abstract]
Limited partners or members ownership interest in company (in hundredths)		36.40%
Unaffiliated Holders [Member]
Ownership structure of AllianceBernstein expressed as a percentage of general and limited partnership interests [Abstract]
Limited partners or members ownership interest in company (in hundredths)		1.40%

Longterm_Incentive_Compensatio1

Long-term Incentive Compensation Plans (Details) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Employee allocation percentage maximum (in hundredths)	50.00%
Long-term incentive cash maximum per employee	$250,000
Long-term incentive awards vesting period	4 years
Period over which holding units are typically distributed to directors	3 years
AB Holding Units purchased in periods (in units)	700,000	200,000
Dollar amount paid for AB Holding Units acquired	17,000,000	3,700,000
Open-market purchases of AB Holding Units (in units)	600,000
Dollar amount paid for open-market purchases of AB Holding Units	15,100,000
Restricted AB Holding Units awarded to employees (in units)	100,000	200,000
Units issued upon exercise of options (in units)	228,816
Proceeds from stock options exercised	3,901,000	4,656,000
Employees Based Outside of the United States [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Employee allocation percentage maximum (in hundredths)	100.00%
Long-term incentive cash maximum per employee	$100,000

Cash_Distributions_Details

Cash Distributions (Details) (USD $)	0 Months Ended	3 Months Ended
	Apr. 30, 2015	Mar. 31, 2015
Cash Distribution [Line Items]
General Partner partnership interest (in hundredths)	1.00%	1.00%
Cash Distribution [Member]
Cash Distribution [Line Items]
Subsequent cash distribution, declaration date	30-Apr-15
Subsequent cash distribution, distribution declared (in dollars per unit)	0.51
General Partner partnership interest (in hundredths)	1.00%
Subsequent cash distribution, distribution date	21-May-15
Subsequent cash distribution, date of record	11-May-15

Real_Estate_Charges_Details

Real Estate Charges (Details) (USD $)	3 Months Ended			12 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014	Sep. 30, 2012	Dec. 31, 2014	Dec. 31, 2010
			sqft		sqft
					Location
Real Estate Charges [Abstract]
Area of office space to be sub-leased (in square feet)			510,000		380,000
Portion of office space subleased (in hundredths)			90.00%
Consolidated number of office locations in New York					2
Number of Locations					3
Portion of office space to be subleased in New York (in hundredths)			70.00%
Pre-Tax real estate credits	$383	($1,942)
Real estate liability restructuring reserve [Abstract]
Balance as of beginning of period	148,429	199,527		199,527
Expense (credit) incurred	139			-4,755
Deferred rent	0			0
Payments made	-11,562			-50,893
Interest accretion	1,082			4,550
Balance as of end of period	$138,088			$148,429

Net_Income_per_Unit_Details

Net Income per Unit (Details) (USD $)	0 Months Ended	3 Months Ended
In Thousands, except Share data, unless otherwise specified	Apr. 30, 2015	Mar. 31, 2015	Mar. 31, 2014
Net Income per Unit [Abstract]
General Partner partnership interest (in hundredths)	1.00%	1.00%
Limited Partners interest in Company (in hundredths)		99.00%
Net income per unit, basic and diluted [Abstract]
Net income attributable to AB Unitholders		$141,469	$116,725
Weighted average units outstanding - basic (in units)		272,831,000	268,459,000
Dilutive effect of compensatory options to buy AB Holding Units (in units)		1,098,000	1,077,000
Weighted average units outstanding - diluted (in units)		273,929,000	269,536,000
Basic net income per AB Unit (in dollars per unit)		$0.51	$0.43
Diluted net income per AB Unit (in dollars per unit)		$0.51	$0.43
Options excluded from diluted net income per unit computation due to their anti-dilutive effect (in units)		2,774,117	2,828,033

Cash_and_Securities_Segregated1

Cash and Securities Segregated Under Federal Regulations and Other Requirements (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
Cash and Securities Segregated Under Federal Regulations and Other Requirements [Abstract]
United States Treasury Bills in special reserve bank custody account for exclusive benefit of brokerage customers of SCB LLC	$500,000,000	$400,000,000
Restricted funds held for benefit of customers by AllianceBernstein Investments, Inc.	$50,200,000	$61,300,000

Investments_Details

Investments (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Summary of Investment Holdings [Line Items]
Investments owned	$728,751		$763,475
Long-term incentive compensation obligations	80,546		98,779
Net Realized and Unrealized Gain (Loss) on Trading Securities [Abstract]
Net gains recognized during the period	6,784	14,812
Less: net gains recognized during the period on trading securities sold during the period	6,047	4,404
Unrealized gains recognized during the period on trading securities held	737	10,408
Consolidated Private Equity Fund [Member]
Summary of Investment Holdings [Line Items]
Investments owned	34,130		32,604
Percentage of seed capital (in hundredths)	10.00%		10.00%
Private Equity [Member]
Summary of Investment Holdings [Line Items]
Investments owned	48,724		48,734
Available-for-Sale Investments [Member]
Summary of Investment Holdings [Line Items]
Investments owned	6,442		6,172
Trading Investments [Member] | Long-term Incentive Compensation-Related [Member]
Summary of Investment Holdings [Line Items]
Investments owned	60,594		74,095
Trading Investments [Member] | Equities [Member]
Summary of Investment Holdings [Line Items]
Investments owned	59,508		79,720
Trading Investments [Member] | Exchange Traded Options [Member]
Summary of Investment Holdings [Line Items]
Investments owned	6,767		22,290
Trading Investments [Member] | U.S Treasury Bills [Member]
Summary of Investment Holdings [Line Items]
Investments owned	28,995		28,982
Trading Investments [Member] | Seed Capital [Member]
Summary of Investment Holdings [Line Items]
Investments owned	425,805		400,746
Investments in Limited Partnership Hedge Funds [Member] | Long-term Incentive Compensation-Related [Member]
Summary of Investment Holdings [Line Items]
Investments owned	19,952		24,684
Investments in Limited Partnership Hedge Funds [Member] | Seed Capital [Member]
Summary of Investment Holdings [Line Items]
Investments owned	26,366		33,951
Other Investment [Member]
Summary of Investment Holdings [Line Items]
Investments owned	$11,468		$11,497

Derivative_Instruments_Details

Derivative Instruments (Details) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Derivative [Line Items]
Net (losses) on derivative instruments	($6,055,000)	($5,521,000)
Cash collateral in brokerage accounts	-11,931,000		-13,241,000
Cash collateral payable to trade counterparties	-1,078,000		-990,000
Losses on equity options activity	32,800,000	60,700,000
Exchange Traded Options [Member] | Long [Member]
Derivative [Line Items]
Derivative Assets	6,800,000		22,300,000
Exchange Traded Options [Member] | Short [Member]
Derivative [Line Items]
Derivative Liabilities	5,600,000		7,100,000
Exchange-Traded Futures [Member]
Derivative [Line Items]
Net (losses) on derivative instruments	-4,987,000	-498,000
Currency Forwards [Member]
Derivative [Line Items]
Net (losses) on derivative instruments	3,452,000	-1,666,000
Interest Rate Swaps [Member]
Derivative [Line Items]
Net (losses) on derivative instruments	-745,000	-793,000
Credit Default Swaps [Member]
Derivative [Line Items]
Net (losses) on derivative instruments	-57,000	-5,000
Option Swaps [Member]
Derivative [Line Items]
Net (losses) on derivative instruments	-17,000	-35,000
Total Return Swaps [Member]
Derivative [Line Items]
Net (losses) on derivative instruments	-3,701,000	-2,524,000
Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Notional Value	674,296,000		508,405,000
Derivative Assets	8,551,000		6,787,000
Derivative Liabilities	9,773,000		9,392,000
Not Designated as Hedging Instrument [Member] | Exchange-Traded Futures [Member]
Derivative [Line Items]
Notional Value	143,141,000		149,863,000
Derivative Assets	360,000		571,000
Derivative Liabilities	3,011,000		2,438,000
Not Designated as Hedging Instrument [Member] | Currency Forwards [Member]
Derivative [Line Items]
Notional Value	204,894,000		149,282,000
Derivative Assets	1,948,000		1,782,000
Derivative Liabilities	963,000		333,000
Not Designated as Hedging Instrument [Member] | Interest Rate Swaps [Member]
Derivative [Line Items]
Notional Value	59,126,000		50,591,000
Derivative Assets	1,909,000		1,507,000
Derivative Liabilities	3,045,000		2,679,000
Not Designated as Hedging Instrument [Member] | Credit Default Swaps [Member]
Derivative [Line Items]
Notional Value	165,028,000		32,745,000
Derivative Assets	3,881,000		1,432,000
Derivative Liabilities	293,000		110,000
Not Designated as Hedging Instrument [Member] | Option Swaps [Member]
Derivative [Line Items]
Notional Value	11,000		11,000
Derivative Assets	11,000		107,000
Derivative Liabilities	0		88,000
Not Designated as Hedging Instrument [Member] | Total Return Swaps [Member]
Derivative [Line Items]
Notional Value	102,096,000		125,913,000
Derivative Assets	442,000		1,388,000
Derivative Liabilities	$2,461,000		$3,744,000

Offsetting_Assets_and_Liabilit2

Offsetting Assets and Liabilities (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Derivative Asset [Abstract]
Cash Collateral Received	($1,078)	($990)
Securities Borrowed [Member]
Securities Borrowed [Abstract]
Gross Amounts of Recognized Assets	157,916	158,147
Gross Amounts Offset in the Statement of Financial Position	0	0
Net Amounts of Assets Presented in the Statement of Financial Position	157,916	158,147
Financial Instruments	0	0
Cash Collateral Received	-157,916	-158,147
Net Amount	0	0
Derivatives [Member]
Derivative Asset [Abstract]
Gross Amounts of Recognized Assets	8,551	6,787
Gross Amounts Offset in the Statement of Financial Position	0	0
Net Amounts of Assets Presented in the Statement of Financial Position	8,551	6,787
Financial Instruments	0	0
Cash Collateral Received	-1,078	-990
Net Amount	7,473	5,797
Exchange Traded Options [Member] | Long [Member]
Derivative Asset [Abstract]
Gross Amounts of Recognized Assets	6,767	22,290
Gross Amounts Offset in the Statement of Financial Position	0	0
Net Amounts of Assets Presented in the Statement of Financial Position	6,767	22,290
Financial Instruments	0	0
Cash Collateral Received	0	0
Net Amount	$6,767	$22,290

Offsetting_Assets_and_Liabilit3

Offsetting Assets and Liabilities, Offsetting Liabilities (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Derivative Liability [Abstract]
Cash Collateral Pledged	($11,931)	($13,241)
Securities Loaned [Member]
Securities Loaned [Abstract]
Gross Amounts of Recognized Liabilities	2,184	33,645
Gross Amounts Offset in the Statement of Financial Position	0	0
Net Amounts of Liabilities Presented in the Statement of Financial Position	2,184	33,645
Financial Instruments	0	0
Cash Collateral Pledged	-2,184	-33,645
Net Amount	0	0
Derivatives [Member]
Derivative Liability [Abstract]
Gross Amounts of Recognized Liabilities	9,773	9,392
Gross Amounts Offset in the Statement of Financial Position	0	0
Net Amounts of Liabilities Presented in the Statement of Financial Position	9,773	9,392
Financial Instruments	0	0
Cash Collateral Pledged	-9,773	-9,392
Net Amount	0	0
Exchange Traded Options [Member] | Short [Member]
Derivative Liability [Abstract]
Gross Amounts of Recognized Liabilities	5,602	7,118
Gross Amounts Offset in the Statement of Financial Position	0	0
Net Amounts of Liabilities Presented in the Statement of Financial Position	5,602	7,118
Financial Instruments	0	0
Cash Collateral Pledged	0	0
Net Amount	$5,602	$7,118

Fair_Value_Details

Fair Value (Details) (USD $)	3 Months Ended		12 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
	Acquisition
Fair value measurement Level 3 reconciliation [Abstract]
Balance as of beginning of period	$58,926,000	$52,081,000	$52,081,000
Transfers out	-26,000	0
Purchases	122,000	501,000
Sales	0	-1,121,000
Realized (losses) gains, net	-5,194,000	1,121,000
Unrealized gains (losses), net	5,013,000	-1,838,000
Balance as of end of period	58,841,000	50,744,000
Percentage of consolidated venture capital fund non-controlling interests owned (in hundredths)	90.00%
Quantitative information about Level 3 fair value measurements [Abstract]
Number of acquisition	3
Fair Value, Liabilities Measurement Level 3 reconciliation
Balance as of beginning of period	42,436,000	38,205,000	38,205,000
Accretion	443,000	321,000
Payments	-656,000	-838,000
Balance as of end of period	42,223,000	37,688,000
Minimum [Member]
Quantitative information about Level 3 fair value measurements [Abstract]
Discount rate (in hundredths)	3.00%
Maximum [Member]
Quantitative information about Level 3 fair value measurements [Abstract]
Discount rate (in hundredths)	18.00%
Weighted Average [Member]
Quantitative information about Level 3 fair value measurements [Abstract]
AUM growth rate (in hundredths)	46.00%
Revenue growth rate (in hundredths)	71.00%
Private Equity Technology, Media and Telecommunications [Member]
Quantitative information about Level 3 fair value measurements [Abstract]
Description of investment	communications, consumer, digital media, healthcare and information technology markets
Private equity investment at fair value	31,000,000
Unfunded commitments to investments	2,900,000
Private Equity Healthcare and Cleantech [Member]
Quantitative information about Level 3 fair value measurements [Abstract]
Number of investment	2		2
Fair value of investments	100,000		200,000
Private Equity Fund [Member]
Quantitative information about Level 3 fair value measurements [Abstract]
Fair value of investments	7,500,000		7,500,000
Description of investment	energy sector
Consolidated Private Equity Investment Venture Capital Fund [Member]
Quantitative information about Level 3 fair value measurements [Abstract]
Description of investment	clean energy, resource and energy efficiency and other sustainable industries
Private equity investment at fair value	100,000
Unfunded commitments to investments	0
Consolidated Private Equity Fund [Member]
Securities sold not yet purchased [Abstract]
Percentage of consolidated venture capital fund the Company owned (in hundredths)	10.00%		10.00%
Fair Value, Measurements, Recurring [Member]
Assets, Fair Value Disclosure [Abstract]
Money markets	172,415,000		89,566,000
U.S. Treasury bills	499,059,000		444,152,000
Available-for-sale [Abstract]
Equity securities	6,136,000		5,951,000
Fixed income securities	306,000		221,000
Trading [Abstract]
Equity securities	359,594,000		387,502,000
Fixed income securities	186,313,000		167,059,000
Long exchange-traded options	6,767,000		22,290,000
Derivatives	8,551,000		6,787,000
Private equity	72,604,000		71,088,000
Total assets measured at fair value	1,311,745,000		1,194,616,000
Securities sold not yet purchased [Abstract]
Short equities - corporate	61,302,000		81,784,000
Short exchange-traded options	5,602,000		7,118,000
Derivatives	9,773,000		9,392,000
Contingent payment arrangements	42,223,000		42,436,000
Total liabilities measured at fair value	118,900,000		140,730,000
Fair Value, Measurements, Recurring [Member] | Private Equity Technology, Media and Telecommunications [Member]
Quantitative information about Level 3 fair value measurements [Abstract]
Fair value	20,044,000		20,112,000
Valuation technique	Market comparable companies		Market comparable companies
Marketability discount (in hundredths)	30.00%
Discount rate (in hundredths)			18.00%
Discount years			2 years
Fair Value, Measurements, Recurring [Member] | Private Equity Technology, Media and Telecommunications [Member] | Minimum [Member]
Quantitative information about Level 3 fair value measurements [Abstract]
Revenue multiple	2.1		2
Fair Value, Measurements, Recurring [Member] | Private Equity Technology, Media and Telecommunications [Member] | Maximum [Member]
Quantitative information about Level 3 fair value measurements [Abstract]
Revenue multiple	4.6		3.5
Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
Assets, Fair Value Disclosure [Abstract]
Money markets	172,415,000		89,566,000
U.S. Treasury bills	0		0
Available-for-sale [Abstract]
Equity securities	6,136,000		5,951,000
Fixed income securities	306,000		221,000
Trading [Abstract]
Equity securities	334,792,000		387,495,000
Fixed income securities	183,227,000		164,317,000
Long exchange-traded options	6,767,000		22,290,000
Derivatives	360,000		571,000
Private equity	13,885,000		12,162,000
Total assets measured at fair value	717,888,000		682,573,000
Securities sold not yet purchased [Abstract]
Short equities - corporate	61,302,000		81,784,000
Short exchange-traded options	5,602,000		7,118,000
Derivatives	3,011,000		2,438,000
Contingent payment arrangements	0		0
Total liabilities measured at fair value	69,915,000		91,340,000
Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
Assets, Fair Value Disclosure [Abstract]
Money markets	0		0
U.S. Treasury bills	499,059,000		444,152,000
Available-for-sale [Abstract]
Equity securities	0		0
Fixed income securities	0		0
Trading [Abstract]
Equity securities	24,680,000		7,000
Fixed income securities	3,086,000		2,742,000
Long exchange-traded options	0		0
Derivatives	8,191,000		6,216,000
Private equity	0		0
Total assets measured at fair value	535,016,000		453,117,000
Securities sold not yet purchased [Abstract]
Short equities - corporate	0		0
Short exchange-traded options	0		0
Derivatives	6,762,000		6,954,000
Contingent payment arrangements	0		0
Total liabilities measured at fair value	6,762,000		6,954,000
Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
Assets, Fair Value Disclosure [Abstract]
Money markets	0		0
U.S. Treasury bills	0		0
Available-for-sale [Abstract]
Equity securities	0		0
Fixed income securities	0		0
Trading [Abstract]
Equity securities	122,000		0
Fixed income securities	0		0
Long exchange-traded options	0		0
Derivatives	0		0
Private equity	58,719,000		58,926,000
Total assets measured at fair value	58,841,000		58,926,000
Securities sold not yet purchased [Abstract]
Short equities - corporate	0		0
Short exchange-traded options	0		0
Derivatives	0		0
Contingent payment arrangements	42,223,000		42,436,000
Total liabilities measured at fair value	$42,223,000		$42,436,000

Commitments_and_Contingencies_

Commitments and Contingencies (Details)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2012	Mar. 31, 2012	Mar. 31, 2012	Mar. 31, 2012
	USD ($)	GBP (£)	Alleged Damages - Minimum [Member]	Alleged Damages - Maximum [Member]
			USD ($)	USD ($)
Loss Contingencies [Line Items]
Portfolio amount of client seeking damages		£ 500
Damages sought			177	234
Realized losses in the portfolio	$125

Units_Outstanding_Details

Units Outstanding (Details)	3 Months Ended
	Mar. 31, 2015
Limited Partners' Capital Account [Line Items]
Outstanding, Beginning of Period (in units)	273,040,452
Options exercised (in units)	228,816
Units issued (in units)	27,755
Units retired (in units)	-689,430
Outstanding, End of Period (in units)	272,607,593
AllianceBernstein Units [Member]
Limited Partners' Capital Account [Line Items]
Units retired (in units)	-400

Debt_Details

Debt (Details) (USD $)	3 Months Ended	12 Months Ended
	Mar. 31, 2015	Dec. 31, 2014
Short-term Debt [Line Items]
Short-term debt outstanding	$500,582,000	$488,988,000
Commercial Paper [Member]
Short-term Debt [Line Items]
Short-term debt outstanding	500,600,000	489,000,000
Weighted average interest rates on short-term debt outstanding (in hundredths)	0.30%	0.30%
Average daily borrowings	$423,900,000	$335,000,000
Weighted average interest rates on average daily borrowings (in hundredths)	0.30%	0.20%

Changes_in_Capital_Details

Changes in Capital (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Changes in capital [Roll Forward]
Beginning balance	$4,085,465
Beginning balance	30,396
Beginning balance	4,115,861
Comprehensive income [Abstract]
Net income	142,744	118,538
Other comprehensive income, net of tax [Abstract]
Foreign currency translation adjustments	-12,275	2,149
Distributions to General Partner and unitholders	-173,075	-178,994
Purchases of AB Units	-11	-229
Ending balance	4,038,835
Ending balance	31,807
Ending balance	4,070,642
Partners Capital Attributable to AB Unitholders [Member]
Changes in capital [Roll Forward]
Beginning balance	4,085,465	4,027,486
Comprehensive income [Abstract]
Net income	141,469	116,725
Other comprehensive income, net of tax [Abstract]
Unrealized gains on investments	308	289
Foreign currency translation adjustments	-12,208	2,108
Changes in employee benefit related items	175	-833
Comprehensive income	129,744	118,289
Distributions to General Partner and unitholders	-173,075	-178,994
Capital contributions from affiliates	6,354	6,209
Purchases of AB Units		-229
Compensation-related transactions	-9,642	7,398
Other	-11
Ending balance	4,038,835	3,980,159
Non-Controlling Interests in Consolidated Entities [Member]
Changes in capital [Roll Forward]
Beginning balance	30,396	42,240
Comprehensive income [Abstract]
Net income	1,275	1,813
Other comprehensive income, net of tax [Abstract]
Unrealized gains on investments	0	0
Foreign currency translation adjustments	-67	41
Changes in employee benefit related items	0	0
Comprehensive income	1,208	1,854
Distributions to General Partner and unitholders	0	0
Capital contributions from affiliates	0	0
Purchases of AB Units		0
Compensation-related transactions	0	0
Other	203
Ending balance	31,807	44,094
Total Capital [Member]
Changes in capital [Roll Forward]
Beginning balance	4,115,861	4,069,726
Comprehensive income [Abstract]
Net income	142,744	118,538
Other comprehensive income, net of tax [Abstract]
Unrealized gains on investments	308	289
Foreign currency translation adjustments	-12,275	2,149
Changes in employee benefit related items	175	-833
Comprehensive income	130,952	120,143
Distributions to General Partner and unitholders	-173,075	-178,994
Capital contributions from affiliates	6,354	6,209
Purchases of AB Units		-229
Compensation-related transactions	-9,642	7,398
Other	192
Ending balance	$4,070,642	$4,024,253

Acquisitions_Details

Acquisitions (Details) (USD $)	0 Months Ended
	Jun. 20, 2014	Mar. 31, 2015	Dec. 31, 2014
Business Acquisition [Line Items]
Goodwill		$3,044,807,000	$3,044,807,000
Redeemable non controlling interest		16,504,000	16,504,000
CPH Capital Fondsmaeglerselskab A/S [Member]
Business Acquisition [Line Items]
Ownership percentage (in hundredths)	82.00%
Assets under management	3,000,000,000
Cash paid	64,400,000
Net contingent consideration payable	9,400,000
Goodwill	58,100,000
Definite-lived intangible assets	24,100,000
Indefinite-lived intangible assets acquired	3,500,000
Redeemable non controlling interest	$16,500,000