Affiliated Managers (MGR) 10-K 25 Feb 16 2015 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2015	Feb. 22, 2016	Jun. 30, 2015
Document and Entity Information
Entity Registrant Name	AFFILIATED MANAGERS GROUP, INC.
Entity Central Index Key	1,004,434
Document Type	10-K
Document Period End Date	Dec. 31, 2015
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Public Float			$ 11,842,794,467
Entity Common Stock, Shares Outstanding		53,991,797
Document Fiscal Year Focus	2,015
Document Fiscal Period Focus	FY

CONSOLIDATED STATEMENTS OF INCO

CONSOLIDATED STATEMENTS OF INCOME - USD ($) shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Statement [Abstract]
Revenue	$ 2,484.5	$ 2,510.9	$ 2,188.8
Operating expenses:
Compensation and related expenses	1,027.7	1,030.5	947.5
Selling, general and administrative	443.8	485.5	427.2
Intangible amortization and impairments	115.4	122.2	128.2
Depreciation and other amortization	18.8	16.9	14
Other operating expenses	43.8	40.6	37.8
Total operating expenses	1,649.5	1,695.7	1,554.7
Operating income	835	815.2	634.1
Income from equity method investments	288.9	281.7	307.8
Other non-operating (income) and expenses:
Investment and other (income) expense	(15.3)	(23.3)	(40.8)
Interest expense	88.9	76.6	87.3
Imputed interest expense and contingent payment arrangements	(40.3)	30.1	31.7
Total non-operating (income) and expenses	33.3	83.4	78.2
Income before income taxes	1,090.6	1,013.5	863.7
Income taxes	256.9	227.9	194.1
Net income	833.7	785.6	669.6
Net income (non-controlling interests)	(317.7)	(333.5)	(309.1)
Net income (controlling interest)	$ 516	$ 452.1	$ 360.5
Average shares outstanding - basic (in shares)	54.3	55	53.1
Average shares outstanding - diluted (in shares)	57.2	58.4	56.7
Earnings per share - basic (in dollars per share)	$ 9.49	$ 8.22	$ 6.79
Earnings per share - diluted (in dollars per share)	$ 9.28	$ 8.01	$ 6.55

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Statement of Comprehensive Income [Abstract]
Net income	$ 833.7	$ 785.6	$ 669.6
Other comprehensive income (loss):
Foreign currency translation gain (loss)	(93.2)	(62)	(19.6)
Change in net realized and unrealized gain (loss) on derivative securities, net of tax	1.9	0.3	1
Change in net unrealized gain (loss) on investment securities, net of tax	22.1	3.4	11.5
Other comprehensive income (loss)	(69.2)	(58.3)	(7.1)
Comprehensive income	764.5	727.3	662.5
Comprehensive income (non-controlling interests)	(298.4)	(317.4)	(311.1)
Comprehensive income (controlling interest)	$ 466.1	$ 409.9	$ 351.4

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Assets
Cash and cash equivalents	$ 563.8	$ 550.6
Receivables	391.2	425.9
Investments in marketable securities	199.9	172.6
Other investments	149.3	167.2
Fixed assets, net	114.1	95.4
Goodwill	2,668.4	2,652.8
Acquired client relationships, net	1,686.4	1,778.4
Equity method investments in Affiliates	1,937.1	1,783.5
Other assets	74.6	71.7
Total assets	7,784.8	7,698.1
Liabilities and Equity
Payables and accrued liabilities	729.4	808.3
Senior bank debt	645	855
Senior notes	944.6	736.8
Convertible securities	305.2	303.1
Deferred income taxes, net	565.7	491.7
Other liabilities	213.3	214.5
Total liabilities	$ 3,403.2	$ 3,409.4
Commitments and contingencies (Note 10)
Redeemable non-controlling interests	$ 612.5	$ 645.5
Equity:
Common stock ($0.01 par value, 153.0 shares authorized; 55.8 shares outstanding in 2014 and 2015)	0.6	0.6
Additional paid-in capital	597.2	672.2
Accumulated other comprehensive income (loss)	(18.1)	31.8
Retained earnings	2,679.3	2,163.3
Total stockholders' equity before treasury stock	3,259	2,867.9
Less: Treasury stock, at cost (1.2 shares in 2014 and 2.0 shares in 2015)	(421.9)	(240.9)
Total stockholders’ equity	2,837.1	2,627
Non-controlling interests	932	1,016.2
Total equity	3,769.1	3,643.2
Total liabilities and equity	$ 7,784.8	$ 7,698.1

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares shares in Millions	Dec. 31, 2015	Dec. 31, 2014
Statement of Financial Position [Abstract]
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	153	153
Common stock, shares outstanding (in shares)	55.8	55.8
Treasury stock, shares (in shares)	2	1.2

CONSOLIDATED STATEMENTS OF CHAN

CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY - USD ($) shares in Millions, $ in Millions	Total	Common Stock	Additional Paid-In Capital	Accumulated Other Comprehensive Income (Loss)	Retained Earnings	Treasury Stock	Non-Controlling Interests
Beginning balance (in shares) at Dec. 31, 2012	53.9
Beginning Balance at Dec. 31, 2012	$ 3,041.4	$ 0.5	$ 868.5	$ 79.1	$ 1,350.7	$ (214.6)	$ 957.2
Increase (Decrease) in Stockholders' Equity
Net income	669.6				360.5		309.1
Other comprehensive income (loss)	(7.1)			(5.1)			(2)
Share-based compensation	27.5		27.5
Common stock issued under share-based incentive plans	45.7		(53.2)			98.9
Tax benefit from share-based incentive plans	20.7		20.7
Settlement of senior convertible securities	(130.7)		(130.7)
Repurchases	(15.7)					(15.7)
Forward equity	(44)		(44)
Affiliate equity activity:
Affiliate equity expense	50.6		34.7				15.9
Issuances	11		(19.9)				30.9
Repurchases	(53.8)		(32.9)				(20.9)
Changes in Redemption value of Redeemable non-controlling interests	(190.8)		(190.8)
Transfers to Redeemable non-controlling interests	(19.5)						(19.5)
Capital Contributions by Affiliate equity holders	6.8						6.8
Distributions to non-controlling interests	$ (267.1)						(267.1)
Ending balance (in shares) at Dec. 31, 2013	53.9
Ending Balance at Dec. 31, 2013	$ 3,144.6	$ 0.5	479.9	74	1,711.2	(131.4)	1,010.4
Increase (Decrease) in Stockholders' Equity
Net income	785.6				452.1		333.5
Other comprehensive income (loss)	(58.3)			(42.2)			(16.1)
Share-based compensation	29.3		29.3
Common stock issued under share-based incentive plans	(5.3)		(134.4)			129.1
Tax benefit from share-based incentive plans	$ 60.2		60.2
Settlement of senior convertible securities (in shares)	1.9	1.9
Settlement of senior convertible securities	$ 276.5	$ 0.1	276.4
Repurchases	(238.6)					(238.6)
Forward equity	(45)		(45)
Investments in Affiliates	235						235
Affiliate equity activity:
Affiliate equity expense	66.2		29.2				37
Issuances	10.8						10.8
Repurchases	0		19.6				(19.6)
Changes in Redemption value of Redeemable non-controlling interests	(43)		(43)
Transfers to Redeemable non-controlling interests	(22.7)						(22.7)
Capital Contributions by Affiliate equity holders	17.3						17.3
Distributions to non-controlling interests	$ (569.4)						(569.4)
Ending balance (in shares) at Dec. 31, 2014	55.8
Ending Balance at Dec. 31, 2014	$ 3,643.2	0.6	672.2	31.8	2,163.3	(240.9)	1,016.2
Increase (Decrease) in Stockholders' Equity
Net income	833.7				516		317.7
Other comprehensive income (loss)	(69.2)			(49.9)			(19.3)
Share-based compensation	34.2		34.2
Common stock issued under share-based incentive plans	54		(131)			185
Tax benefit from share-based incentive plans	44.5		44.5
Repurchases	(366)					(366)
Forward equity	0
Investments in Affiliates	33.8						33.8
Affiliate equity activity:
Affiliate equity expense	62		10.4				51.6
Issuances	1.7		0.1				1.6
Repurchases	48		48.4				(0.4)
Changes in Redemption value of Redeemable non-controlling interests	(81.6)		(81.6)
Transfers to Redeemable non-controlling interests	(49.5)						(49.5)
Capital Contributions by Affiliate equity holders	11.7						11.7
Distributions to non-controlling interests	$ (431.4)						(431.4)
Ending balance (in shares) at Dec. 31, 2015	55.8
Ending Balance at Dec. 31, 2015	$ 3,769.1	$ 0.6	$ 597.2	$ (18.1)	$ 2,679.3	$ (421.9)	$ 932

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Cash flow from (used in) operating activities:
Net income	$ 833.7	$ 785.6	$ 669.6
Adjustments to reconcile Net income to net cash flow from operating activities:
Intangible amortization and impairments	115.4	122.2	128.2
Depreciation and other amortization	18.8	16.9	14
Deferred income tax provision	94.7	62.8	27.7
Imputed interest expense and contingent payment arrangements	(40.3)	30.1	31.7
Income from equity method investments, net of amortization	(288.9)	(281.7)	(307.8)
Distributions received from equity method investments	346.1	366.9	226.6
Amortization of issuance costs	8.1	7.6	9.6
Share-based compensation and Affiliate equity expense	102.7	113.7	84.1
Other non-cash items	(5.8)	3.8	10.4
Changes in assets and liabilities:
(Increase) decrease in receivables	56.1	26.5	(101.8)
(Increase) decrease in other assets	6.2	(7.1)	(12.8)
Increase (decrease) in payables, accrued liabilities and other liabilities	(42)	144.9	177.6
Cash flow from operating activities	1,204.8	1,392.2	957.1
Cash flow from (used in) investing activities:
Investments in Affiliates	(297.7)	(1,245)	(26.3)
Purchase of fixed assets	(38.2)	(19.2)	(24)
Purchase of investment securities	(13.5)	(21.2)	(11.4)
Sale of investment securities	24.9	17.3	11.4
Cash flow used in investing activities	(324.5)	(1,268.1)	(50.3)
Cash flow from (used in) financing activities:
Borrowings of senior debt	1,253.3	1,746.5	760
Repayments of senior debt and convertible securities	(1,256)	(1,020.6)	(1,201.3)
Issuance of common stock	57.8	41.4	48.2
Repurchase of common stock	(413.7)	(190.8)	(15.7)
Note and contingent payments	20.5	14.4	(41)
Distributions to non-controlling interests	(431.4)	(569.4)	(267.1)
Affiliate equity issuances and repurchases	(120.6)	(65.7)	(118.1)
Excess tax benefit from share-based compensation	44.5	61.5	17.3
Settlement of forward equity sale agreement	0.1	(45)	(44)
Other financing items	(8.6)	(5.2)	(7.4)
Cash flow used in financing activities	(854.1)	(32.9)	(869.1)
Effect of foreign exchange rate changes on cash and cash equivalents	(13)	(10.2)	1.5
Net increase (decrease) in cash and cash equivalents	13.2	81	39.2
Cash and cash equivalents at beginning of period	550.6	469.6	430.4
Cash and cash equivalents at end of period	563.8	550.6	469.6
Supplemental disclosure of cash flow information:
Interest paid	76.4	67.9	87.4
Income taxes paid	89.6	110.7	82.8
Supplemental disclosure of non-cash financing activities:
Settlement of 2006 junior convertible securities	0	217.8	0
Stock issued under incentive plans	10.7	63.6	1.3
Stock received in settlement of liability	3.6	44.7	0.5
Payables recorded for Share repurchases	0	47.8	0
Payables recorded for Affiliate equity repurchases	$ 62.3	$ 21.5	$ 4

Business and Summary of Signifi

Business and Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2015
Accounting Policies [Abstract]
Business and Summary of Significant Accounting Policies	Business and Summary of Significant Accounting Policies (a) Organization and Nature of Operations Affiliated Managers Group, Inc. (“AMG” or the “Company”) is a global asset management company with equity investments in leading boutique investment management firms, referred to as “Affiliates.” AMG’s Affiliates provide investment management services globally to institutional clients, mutual funds and high net worth individuals. Each of AMG’s Affiliates operate through distinct entities, typically organized as limited liability companies or limited partnerships (or equivalent non-U.S. forms), which affords AMG the flexibility to design a separate operating agreement for each Affiliate. The operating agreements reflect the specific terms of AMG’s economic participation in the Affiliate (a “structured partnership interest”). AMG’s structured partnership interests consist primarily of structures through which AMG shares in the Affiliate’s revenue without regard to expenses. AMG’s structured partnership interests also include structures through which AMG shares in the Affiliate’s revenue less certain agreed-upon expenses. When AMG owns a majority of the equity interests in an Affiliate and shares in the Affiliate’s revenue without regard to expenses, a set percentage of revenue is allocated to fund operating expenses, including compensation (the “Operating Allocation”), while the remaining revenue (the “Owners’ Allocation”) is allocated to AMG and Affiliate management in proportion to their respective ownership interests. When AMG owns a minority of the equity interests in an Affiliate and shares in the Affiliate’s revenue without regard to expenses, AMG is allocated a set percentage of revenue, with the remaining revenue allocated to fund operating expenses and distributions to Affiliate management. When AMG’s structured partnership interest is calculated by reference to an Affiliate’s revenue less certain agreed upon expenses, whether AMG owns a majority or minority of the equity interests, AMG is allocated a set percentage of the Affiliate’s revenue net of the agreed categories of expenses. (b) Basis of Presentation and Use of Estimates The financial statements are prepared in accordance with accounting principles generally accepted in the U.S. (“GAAP”). All dollar amounts, except per share data in the text and tables herein, are stated in millions unless otherwise indicated. Certain reclassifications have been made to prior years’ financial statements to conform to the current year’s presentation. The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts and disclosures in the financial statements. Actual results could differ from those estimates. (c) Principles of Consolidation Investments in Affiliates The Company evaluates the risk, rewards, and significant terms of each of its Affiliate and other investments to determine the appropriate method of accounting. Majority-owned or otherwise controlled investments are consolidated and all material intercompany balances and transactions are eliminated. For its consolidated Affiliates, the portion of the Owners’ Allocation allocated to Affiliate management is included in Net income (non-controlling interests) in the Consolidated Statements of Income. Non-controlling interests on the Consolidated Balance Sheets include capital and undistributed Operating and Owners’ Allocation owned by Affiliate management of the consolidated Affiliates. The effect of any changes in the Company’s equity interests in its consolidated Affiliates resulting from the issuance or repurchase of an Affiliate’s equity by the Company or one of its Affiliates is included as a component of stockholders’ equity, net of the related income tax effect in the period of the change. The current redemption value of non-controlling interests has been presented as Redeemable non-controlling interests on the Consolidated Balance Sheets. AMG applies the equity method of accounting to investments where AMG does not hold a controlling equity interest but has the ability to exercise significant influence over operating and financial matters. In cases where AMG applies the equity method of accounting, it does not typically have an obligation to repurchase Affiliate equity interests. Other investments in which AMG owns less than a 20% interest and does not exercise significant influence are accounted for under the cost method. Under the cost method, income is recognized as dividends when, and if, declared. Affiliate-sponsored Investment Vehicles The Company’s Affiliates sponsor various investment vehicles where they also act as the investment advisor. Certain of these investment vehicles are variable interest entities (“VIEs”) while others are voting rights entities (“VREs”). VIEs are consolidated if the Affiliate is determined to be the primary beneficiary (i.e., if it absorbs a majority of the expected losses, or receives a majority of the expected residual returns). In determining whether the Affiliate is the primary beneficiary, both qualitative and quantitative factors (e.g., the voting rights of the equity holders, economic participation of all parties, including how fees are earned and paid, related party ownership, guarantees and implied relationships) are considered. VREs are consolidated if the Affiliate is the managing member or general partner of the investment vehicle unless unaffiliated investors have certain rights to remove the Affiliate from such role, have substantive participating rights or otherwise control the investment vehicle. (d) Cash and Cash Equivalents The Company considers all highly liquid investments, including money market mutual funds, with original maturities of three months or less to be cash equivalents. Cash equivalents are stated at cost, which approximates market value due to the short-term maturity of these investments. (e) Receivables The Company’s Affiliates earn advisory and performance fees, which are billed based on the terms of the related contracts. Billed but uncollected advisory and performance fees are presented within Receivables on the Consolidated Balance Sheets and are generally short-term in nature. Certain of the Company’s Affiliates in the United Kingdom act as an intermediary between clients and their sponsored funds. Normal settlement periods on transactions initiated by these clients result in unsettled fund share receivables and payables that are presented on a gross basis within Receivables and Payables and accrued liabilities on the Consolidated Balance Sheets. The gross presentation of these receivables and offsetting payables reflects the legal relationship between the underlying investor and the Company’s Affiliates. (f) Investments in Marketable Securities Investments in marketable securities are classified as either trading or available-for-sale and carried at fair value. Unrealized gains or losses on investments classified as available-for-sale are reported, net of tax, as a separate component of Accumulated other comprehensive income in Equity until realized when they are reported in Investment and other (income) expense. Realized and unrealized gains or losses related to trading securities are reported within Investment and other (income) expense in the period they occur on a specific identification basis. If a decline in the fair value of an available-for-sale investment is determined to be other than temporary, the carrying amount of the asset is reduced to its fair value, and the difference is charged to income in the period incurred. (g) Fair Value Measurements The Company determines the fair value of certain investment securities and other financial and non-financial assets and liabilities. Fair value is determined based on the price that would be received for an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date, utilizing a hierarchy of three different valuation techniques: Level 1 - Unadjusted quoted market prices for identical instruments in active markets; Level 2 - Quoted prices for similar instruments in active markets; quoted prices for identical or similar instruments in markets that are not active; and model-derived valuations whose inputs, or significant value drivers, are observable; and Level 3 - Prices reflect the Company’s own assumptions concerning unobservable inputs to the valuation model. These inputs require significant management judgment and reflect the Company’s assumptions that market participants would use in pricing the asset or liability. (h) Fixed Assets Fixed assets are recorded at cost and depreciated using the straight-line method over their estimated useful lives. The estimated useful lives of office equipment and furniture and fixtures range from three to ten years . Computer software developed or obtained for internal use is amortized using the straight-line method over the estimated useful life of the software, generally three to seven years. Leasehold improvements are amortized over the shorter of their estimated useful lives or the term of the lease, and buildings are amortized over their expected useful lives. The costs of improvements that extend the life of a fixed asset are capitalized, while the cost of repairs and maintenance are expensed as incurred. Land is not depreciated. (i) Leases The Company and its Affiliates currently lease office space and equipment under various leasing arrangements. As these leases expire, it can be expected that in the normal course of business they will be renewed or replaced. Leases are classified as either capital leases or operating leases, as appropriate. Most lease agreements for office space that are classified as operating leases contain renewal options, rent escalation clauses or other inducements provided by the landlord. Rent expense is accrued to recognize lease escalation provisions and inducements provided by the landlord, if any, on a straight-line basis over the lease term. (j) Equity Investments in Affiliates For equity method investments, the Company’s share of the Affiliate’s revenue without regard to expenses or the Company’s share of the Affiliate’s revenue less certain agreed-upon expenses, net of any amortization of intangible assets related to the Company’s investment, is included in Income from equity method investments. The Company’s share of income taxes incurred directly by Affiliates accounted for under the equity method is recorded within income taxes because these taxes generally represent the Company’s share of the taxes incurred by the Affiliate. The Company periodically evaluates its equity method investments for impairment. In such impairment evaluations, the Company assesses if the fair value of the investment has declined below its carrying value for a period considered to be other than temporary. If the Company determines that a decline in fair value below the carrying value of the investment is other than temporary, then the reduction in carrying value would be recognized in Income from equity method investments in the Consolidated Statements of Income. (k) Acquired Client Relationships and Goodwill Each Affiliate in which the Company makes an investment has identifiable assets arising from contractual or other legal rights with their clients (“acquired client relationships”). In determining the value of acquired client relationships, the Company analyzes the net present value of these Affiliates’ existing client relationships based on a number of factors, including: the Affiliate’s historical and potential future operating performance; the Affiliate’s historical and potential future rates of attrition among existing clients; the stability and longevity of existing client relationships; the Affiliate’s recent, as well as long-term, investment performance; the characteristics of the firm’s products and investment styles; the stability and depth of the Affiliate’s management team; and the Affiliate’s history and perceived franchise or brand value. The Company has determined that certain of its mutual fund acquired client relationships meet the criteria to be considered indefinite-lived assets because the Company expects both the renewal of these contracts and the cash flows generated by these assets to continue indefinitely. Accordingly, the Company does not amortize these intangible assets, but instead reviews these assets annually or more frequently whenever events or circumstances occur indicating that the recorded indefinite-lived assets may be impaired. Each reporting period, the Company assesses whether events or circumstances have occurred that indicate that the indefinite life criteria are no longer met. If the indefinite life criteria are no longer met, the Company would assess whether the carrying value of the assets exceeds its fair value, an impairment loss would be recorded in an amount equal to any such excess and these assets would be reclassified to definite-lived. The expected useful lives of definite-lived acquired client relationships are determined based on an analysis of the historical and projected attrition rates of each Affiliate’s existing clients, and other factors that may influence the expected future economic benefit the Company will derive from the relationships. The expected lives of definite-lived acquired client relationships are analyzed annually or more frequently whenever events or circumstances have occurred that indicate the expected useful lives may no longer be appropriate. The Company tests for the possible impairment of indefinite and definite-lived intangible assets annually or more frequently whenever events or changes in circumstances indicate that the carrying amount of the asset is not recoverable. If such indicators exist, the Company compares the fair value of the asset to the carrying value of the asset. If the carrying value is greater than the fair value, an impairment loss would be recorded in Intangible amortization and impairments. Goodwill represents the future economic benefits arising from assets acquired in a business combination that are not individually identified and separately recognized, and is reported within the segments in which the Affiliate operates. Goodwill is not amortized, but is instead reviewed for impairment. The Company assesses goodwill for impairment at least annually, or more frequently whenever events or circumstances occur indicating that the recorded goodwill may be impaired. If the carrying amount of goodwill exceeds the fair value, an impairment loss would be recorded in Intangible amortization and impairments. (l) Issuance Costs Issuance costs related to Company’s senior bank debt are amortized over the remaining term of the credit facility and term loan. Costs incurred to issue debt are amortized over the shorter of the period to the first investor put or the Company’s estimate of the expected term of the security. Costs associated with financial instruments that are not required to be accounted for separately as derivative instruments are charged directly to stockholders’ equity. (m) Derivative Financial Instruments The Company may utilize financial instruments, specifically interest rate derivative contracts to hedge certain interest rate exposures. In entering into these contracts, the Company intends to offset cash flow gains and losses that occur on its existing debt obligations with cash flow gains and losses on the contracts hedging these obligations. From time to time, the Company’s Affiliates use foreign currency forward contracts to hedge the risk of currency exchange rate movements. In entering into these contracts, the Affiliates intend to offset cash flow gains and losses on projected foreign currency-denominated revenues and expenses as a result of variability in foreign currency exchange rates. The Company records derivatives on the balance sheet at fair value. If the Company’s derivatives qualify as cash flow hedges, the effective portion of the unrealized gain or loss is recorded in Accumulated other comprehensive income as a separate component of stockholders’ equity and reclassified into earnings when the hedged cash flows are recorded in earnings. Hedge effectiveness is generally measured by comparing the present value of the cumulative change in the expected future variable cash flows of the hedged contract with the present value of the cumulative change in the expected future variable cash flows of the hedged item. To the extent that the critical terms of the hedged item and the derivative are not identical, hedge ineffectiveness would be reported in Investment and other (income) expense. If the Company’s derivatives do not qualify as cash flow or fair value hedges, changes in the fair value of the derivatives are recognized as a gain or loss in Investment and other (income) expense. (n) Contingent Payment Arrangements The Company periodically enters into contingent payment arrangements in connection with its business combinations. In these arrangements, the Company agrees to pay additional consideration to the sellers to the extent that certain levels of revenue growth are achieved. For consolidated Affiliates, the Company estimates the fair value of these potential future obligations at the time a business combination is consummated and records a liability on its Consolidated Balance Sheet. The Company then accretes the obligation to its expected payment amount over the period until the arrangement is measured. If the Company’s expected payment amount subsequently changes, the obligation is reduced or increased in the current period resulting in a gain or loss, respectively. Both gains and losses resulting from changes to expected payments and the accretion of these obligations to their expected payment amounts are reflected within Imputed interest expense and contingent payment arrangements in the Company’s Consolidated Statements of Income. For Affiliates accounted for under the equity method, the Company records a liability when a payment becomes probable with a corresponding increase to the carrying value of the Affiliate. (o) Income Taxes The Company accounts for income taxes using the liability method. Under this method, deferred taxes are recognized for the expected future tax consequences of temporary differences between the book carrying amounts and tax bases of the Company’s assets and liabilities. Deferred tax liabilities are generally attributable to intangible assets, convertible securities and deferred income. Deferred tax assets are generally attributable to deferred compensation, state and foreign loss carryforwards, and the benefit of uncertain tax positions. Intangible-related deferred tax liabilities are not recorded on U.S. basis differences related to the Company’s foreign investments in corporate stock because of the permanent nature of the Company’s investments. In measuring the amount of deferred taxes each period, the Company must project the impact on its future tax payments of any reversal of deferred tax liabilities (which would increase the Company’s tax payments), and any use of its state and foreign loss carryforwards (which would decrease its tax payments). In forming these estimates, the Company uses enacted federal, state and foreign income tax rates and makes assumptions about the apportionment of future taxable income to jurisdictions in which the Company has operations. An increase or decrease in foreign, federal or state income tax rates could have a material impact on the Company’s deferred income tax liabilities and assets and would result in a current income tax charge or benefit. The Company recognizes the financial statement benefit of an uncertain tax position only after considering the probability that a tax authority would sustain the position in an examination. For tax positions meeting a “more-likely-than-not” threshold, the amount recognized in the financial statements is the benefit expected to be realized upon settlement with the tax authority. For tax positions not meeting the threshold, no financial statement benefit is recognized. The Company recognizes interest and other charges relating to unrecognized tax benefits as additional tax expense. The Company regularly assesses the need for valuation allowances on its deferred tax assets, which would reduce these assets to their recoverable amounts. In forming these estimates, the Company makes assumptions of future taxable income that may be generated to utilize these assets, which have limited lives. If the Company determines that these assets will be realized, the Company records an adjustment to the valuation allowance, which would decrease tax expense in the period such determination was made. Likewise, should the Company determine that it would be unable to realize additional amounts of deferred tax assets, an adjustment to the valuation allowance would be charged to tax expense in the period such determination was made. The Company operates in various locations outside the U.S. and generates earnings from its foreign subsidiaries. The Company does not recognize a provision for U.S. income taxes or a deferred income tax liability on undistributed foreign earnings that are indefinitely reinvested. (p) Foreign Currency Translation The assets and liabilities of Affiliates whose functional currency is not the U.S. dollar are translated into U.S. dollars using exchange rates in effect as of the balance sheet date. The revenue and expenses of these Affiliates are translated into U.S. dollars using average exchange rates for the relevant period. Because of the permanent nature of the Company’s investments, net translation exchange gains and losses are excluded from Net income and recorded in Other comprehensive income. Foreign currency transaction gains and losses are reflected in Investment and other (income) expense. (q) Concentration of Credit Risk Financial instruments that potentially subject the Company to significant concentrations of credit risk consist principally of cash investments. The Company maintains cash and cash equivalents, investments and, at times, certain financial instruments with various high credit-quality financial institutions. These financial institutions are typically located in countries in which AMG and its Affiliates operate. For AMG and certain Affiliates, cash deposits at a financial institution may exceed Federal Deposit Insurance Corporation insurance limits. (r) Revenue Recognition The Company’s consolidated revenue primarily represents advisory fees billed by Affiliates for managing the assets of clients. Asset-based advisory fees are recognized as services are rendered and are based upon a percentage of the value of client assets managed. Any fees collected in advance are deferred and recognized as income over the period earned. Performance-based advisory fees are generally assessed as a percentage of the investment performance realized on a client’s account, generally over an annual period. Performance-based advisory fees are recognized when they are earned (i.e., when they become billable to customers and are not subject to claw-back) based on the contractual terms of agreements and when collection is reasonably assured. Carried interest is recognized upon the earlier of the termination of the investment product or when the likelihood of claw-back is improbable. Also included in revenue are commissions earned by broker-dealers, recorded on a trade date basis, and other service fees recorded as earned. The Company’s Affiliates have contractual arrangements with third parties to provide certain distribution-related services. These third parties are primarily compensated based on the value of client assets over time. Distribution-related revenues are presented gross of any related expenses when the Affiliate is the principal in its role as primary obligor under its sales and distribution arrangements. Distribution-related expenses are presented within Selling, general and administrative expenses. (s) Earnings Per Share The calculation of basic earnings per share is based on the weighted average number of shares of the Company’s common stock outstanding during the period. Diluted earnings per share is similar to basic earnings per share, but adjusts for the dilutive effect of the potential issuance of incremental shares of the Company’s common stock. The Company had convertible securities outstanding during the periods presented and is required to apply the if-converted method to these securities in its calculation of diluted earnings per share. Under the if-converted method, shares that are issuable upon conversion are deemed outstanding, regardless of whether the securities are contractually convertible into the Company’s common stock at that time. For this calculation, the interest expense (net of tax) attributable to these dilutive securities is added back to Net income (controlling interest), reflecting the assumption that the securities have been converted. Issuable shares for these securities and related interest expense are excluded from the calculation if an assumed conversion would be anti-dilutive to diluted earnings per share. (t) Share-Based Compensation Plans The Company recognizes expenses for all share-based payments based on their grant date fair values over the requisite service period. The Company reports any tax benefits realized upon the exercise of stock options that are in excess of the expense recognized for reporting purposes as a financing activity in the Company’s Consolidated Statements of Cash Flows. If the tax benefit realized is less than the expense, the tax shortfall is recognized in stockholders’ equity. To the extent the expense exceeds available windfall tax benefits, it is recognized in the Consolidated Statements of Income. The Company was permitted to calculate its cumulative windfall tax benefits for the purposes of accounting for future tax shortfalls. The Company elected to apply the long-form method for determining the pool of windfall tax benefits. (u) Segment Information Management has assessed and determined that the Company operates in three business segments representing the Company’s three principal distribution channels: Institutional, Mutual Fund and High Net Worth, each of which has different client relationships. Revenue and income from equity method investments in the Institutional distribution channel is earned from relationships with public and private client entities, including foundations, endowments, sovereign wealth funds and retirement plans for corporations and municipalities. Revenue and income from equity method investments in the Mutual Fund distribution channel is earned from advisory or sub-advisory relationships with active return oriented mutual funds, UCITS and other retail products. Revenue and income from equity method investments in the High Net Worth distribution channel is earned from relationships with high net worth and ultra-high net worth individuals, families, trusts, foundations, endowments and retirement plans. In measuring Net income (controlling interest) by segment, the Company’s share of expenses incurred directly at Affiliates and AMG Funds is allocated to a particular segment pro rata to the revenue generated by the Affiliate and AMG Funds in such segment. All other operating and non-operating expenses not incurred directly by an Affiliate or AMG Funds are generally allocated to segments based on the relative contribution to earnings of the applicable Affiliate or AMG Funds in each segment. (v) Recent Accounting Developments In May 2014, the Financial Accounting Standards Board (the “FASB”) issued a final standard on revenue from contracts with customers. The new standard provides a comprehensive model for revenue recognition. The new standard is effective for interim and fiscal periods beginning after December 15, 2017. The Company is evaluating the impact of this standard on its Consolidated Financial Statements. In February 2015, the FASB issued a new standard that amended the current consolidation guidance. The new standard changes the analysis required to determine whether an entity is a variable interest entity and should be consolidated. The new standard is effective for interim and fiscal periods beginning after December 15, 2015. The Company is evaluating the impact of this new standard on its Consolidated Financial Statements. In April 2015, the FASB issued a new standard to reduce diversity in the presentation of debt issuance costs. The new standard requires debt issuance costs to be presented on the balance sheet as a deduction from the related debt. The new standard is effective for interim and fiscal periods beginning after December 15, 2015. The Company does not anticipate that this new standard will have a material impact on its Consolidated Financial Statements. In April 2015, the FASB issued a new standard amending the disclosure requirements for investments in certain entities that calculate net asset value per share. The new standard removes, from the fair value hierarchy, investments for which the net asset value is used as a practical measure of fair value. The new standard is effective for interim and fiscal periods beginning after December 15, 2015. The Company does not anticipate that this new standard will have a material impact on its Consolidated Financial Statements. In September 2015, the FASB issued a new standard requiring an acquirer to recognize and disclose adjustments to provisional purchase price allocations, performed in connection with business combinations, in the reporting period in which the adjustments are determined. The new standard is effective for interim and fiscal periods beginning after December 15, 2015. The Company is evaluating the impact of this new standard on its Consolidated Financial Statements. In January 2016, the FASB issued a new standard that changes the accounting for equity investments, financial liabilities under the fair value option and the presentation and disclosure requirements for financial instruments. Under the new guidance, all equity investments in unconsolidated entities (other than those accounted for using the equity method of accounting) will generally be measured at fair value through earnings. The new standard is effective for interim and fiscal periods beginning after December 15, 2017. The Company is evaluating the impact of this new standard on its Consolidated Financial Statements.

Investments in Marketable Secur

Investments in Marketable Securities	12 Months Ended
	Dec. 31, 2015
Marketable Securities [Abstract]
Investments in Marketable Securities	Investments in Marketable Securities Investments in marketable securities at December 31, 2014 and 2015 were $172.6 million and $199.9 million , respectively. The following is a summary of the cost, gross unrealized gains and losses and fair value of investments classified as available-for-sale and trading: Available-for-Sale Trading December 31, 2014 December 31, 2015 December 31, 2014 December 31, 2015 Cost $ 125.6 $ 104.7 $ 19.5 $ 19.8 Unrealized Gains 42.8 77.6 2.9 1.9 Unrealized Losses (18.1 ) (1.8 ) (0.1 ) (2.3 ) Fair Value $ 150.3 $ 180.5 $ 22.3 $ 19.4 For the years ended December 31, 2014 and 2015, there were $3.4 million and $8.8 million , respectively, of realized gains on investments classified as available-for-sale. These gains were recorded in Investment and other (income) expense. There were no significant realized gains or losses on investments classified as trading for the years ended December 31, 2014 and 2015.

Other Investments

Other Investments	12 Months Ended
	Dec. 31, 2015
Investments, All Other Investments [Abstract]
Other Investments	Other Investments Other investments consist of investments in funds advised by Affiliates that are carried at fair value. The income or loss related to these investments is classified within Investment and other (income) expense in the Consolidated Statements of Income.

Variable Interest Entities

Variable Interest Entities	12 Months Ended
	Dec. 31, 2015
Variable Interest Entities
Variable Interest Entities	Variable Interest Entities The Company’s consolidated Affiliates act as the investment manager for certain VIEs. These Affiliates are entitled to receive management fees and may be eligible to receive performance fees. The Affiliates’ exposure to risk in these entities is generally limited to any equity investment and any uncollected management or performance fees, neither of which were significant at December 31, 2014 and 2015 . These Affiliates do not have any investment performance guarantees to these VIEs. Consolidated Affiliates are not the primary beneficiaries of any of these VIEs as their involvement is limited to that of a service provider, and their investment, if any, represents an insignificant interest in the relevant fund’s assets under management. Since these Affiliates’ variable interests will not absorb the majority of the variability of the VIE’s net assets, these entities are not consolidated. The net assets and liabilities of these unconsolidated VIEs and the Company’s maximum risk of loss were as follows: December 31, 2014 December 31, 2015 Category of Investment Unconsolidated VIE Net Assets Carrying Value and Maximum Risk of Loss Unconsolidated VIE Net Assets Carrying Value and Maximum Risk of Loss Sponsored investment funds $ 8,550.4 $ 1.2 $ 6,688.9 $ 1.4

Senior Bank Debt

Senior Bank Debt	12 Months Ended
	Dec. 31, 2015
Debt Disclosure [Abstract]
Senior Bank Debt	Senior Bank Debt In 2015, the Company entered into a $1.3 billion senior unsecured multicurrency revolving credit facility (the “revolver”) and a $350.0 million senior unsecured term loan facility (the “term loan” and, together with the revolver, the “credit facilities”). The credit facilities, which replaced previous credit facilities, both mature on September 30, 2020. Subject to certain conditions, the Company may increase commitments under the revolver by up to an additional $500.0 million and may borrow up to an additional $100.0 million under the term loan. The Company pays interest on any outstanding obligations under the revolver and on the term loan at specified rates, based either on the LIBOR rate or the prime rate as in effect from time to time. As of December 31, 2014 and 2015 , the Company had outstanding borrowings under the revolver of $605.0 million and $295.0 million, respectively, and the weighted-average interest rate on outstanding borrowings was 1.40% and 2.52% , respectively. As of December 31, 2014 and 2015 , the Company had outstanding borrowings under the term loan of $250.0 million and $350.0 million , respectively, and the weighted-average interest rate on outstanding borrowings was 1.48% and 1.45% , respectively. The Company pays commitment fees on the unused portion of its revolver. In 2014 and 2015 , these fees amounted to $2.8 million and $1.9 million , respectively. The credit facilities contain financial covenants with respect to leverage and interest coverage, as well as customary affirmative and negative covenants, including limitations on priority indebtedness, asset dispositions and fundamental corporate changes, and to certain customary events of default.

Senior Notes

Senior Notes	12 Months Ended
	Dec. 31, 2015
Debt Disclosure [Abstract]
Senior Notes	Senior Notes In 2015, the Company redeemed, canceled and retired all $140.0 million principal amount outstanding of its 5.25% senior unsecured notes due 2022 at a redemption price equal to 100% of the principal amount plus accrued and unpaid interest. In February 2015, the Company issued additional senior notes, and at December 31, 2015 had three senior notes outstanding, the principal terms of which are summarized below. 2024 Senior Notes 2025 Senior Notes 2042 Senior Notes Issue date February 2014 February 2015 August 2012 Maturity date February 2024 August 2025 August 2042 Potential Call Date Any Time (1) Any Time (1) August 2017 Par value (in millions) $ 400.0 $ 350.0 $ 200.0 Call Price As Defined (1) As Defined (1) At Par Stated coupon 4.25 % 3.50 % 6.375 % Coupon frequency Semi-annually Semi-annually Quarterly __________________________ (1) The 2024 and 2025 senior notes may be redeemed at any time, in whole or in part, at a make-whole redemption price plus accrued and unpaid interest.

Convertible Securities

Convertible Securities	12 Months Ended
	Dec. 31, 2015
Debt Disclosure [Abstract]
Convertible Securities	Convertible Securities In 2014, the Company delivered a notice to redeem all $300.0 million principal amount of its outstanding junior convertible trust preferred securities issued in 2006 (“2006 junior convertible securities”). In lieu of redemption, substantially all holders of the 2006 junior convertible securities elected to convert their securities into a defined number of shares. The Company issued 1.9 million shares of its common stock and recognized a loss of $18.8 million , which is included in Imputed interest expense and contingent payment arrangements. All of the Company’s 2006 junior convertible securities have been canceled and retired. At December 31, 2015 , the Company had junior convertible trust preferred securities outstanding that were issued in 2007 (“2007 junior convertible securities”). The carrying values of the Company’s convertible securities were as follows: December 31, 2014 December 31, 2015 Carrying Value Principal Amount at Maturity Carrying Value Principal Amount at Maturity 2007 junior convertible securities (1) $ 303.1 $ 430.8 $ 305.2 $ 430.8 __________________________ (1) The carrying value is accreted to the principal amount at maturity over a remaining life of 22 years. The 2007 junior convertible securities bear interest at 5.15% per annum, payable quarterly in cash. Each $ 50 security is convertible, at any time, into 0.25 shares of the Company’s common stock, which represents a conversion price of $200 per share. Holders of the securities have no rights to put these securities to the Company. Upon conversion, holders will receive cash or shares of the Company’s common stock, or a combination thereof, at the Company’s election. The Company may redeem the 2007 junior convertible securities if the closing price of its common stock exceeds $260 per share for 20 trading days in a period of 30 consecutive trading days. These convertible securities are considered contingent payment debt instruments under federal income tax regulations, which require the Company to deduct interest in an amount greater than its reported interest expense. These deductions result in annual deferred tax liabilities of $9.4 million . These deferred tax liabilities will be reclassified directly to stockholders’ equity if the Company’s common stock is trading above certain thresholds at the time of the conversion of the securities.

Forward Equity Sale Agreement

Forward Equity Sale Agreement	12 Months Ended
	Dec. 31, 2015
Forward Equity Sale Agreements
Forward Equity Sale Agreement	Forward Equity Sale Agreement The Company may sell shares of its common stock under a forward equity agreement. At December 31, 2015, the Company had approximately $250 million remaining notional amount that was available to sell under the forward equity agreement.

Derivative Financial Instrument

Derivative Financial Instruments	12 Months Ended
	Dec. 31, 2015
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Financial Instruments	Derivative Financial Instruments From time to time, the Company seeks to offset its exposure to changing interest rates under its debt financing arrangements and certain of its Affiliates seek to offset their exposure to changing foreign currency exchange rates by entering into derivative contracts. During 2015, the Company’s Affiliates realized $3.2 million of gains and $1.7 million of losses upon the settlement of certain foreign currency forward contracts. Such realized gains and losses are presented in the Consolidated Statements of Income within Revenue, Investment and other (income) expense or Operating expenses, depending on the risk being hedged.

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2015
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies From time to time, the Company and its Affiliates may be subject to claims, legal proceedings and other contingencies in the ordinary course of their business activities. Any such matters are subject to various uncertainties, and it is possible that some of these matters may be resolved in a manner unfavorable to the Company or its Affiliates. The Company and its Affiliates establish accruals, as necessary, for matters for which the outcome is probable and the amount of the liability can be reasonably estimated. The Company had no significant accruals as of December 31, 2015. In the first quarter of 2016, Third Avenue Management LLC (“Third Avenue”), one of the Company’s consolidated Affiliates, was named as a defendant in various legal actions relating to the liquidation and closure of the Third Avenue Focused Credit Fund. The Company is not a party to any of these actions. Third Avenue believes that the claims in these actions are without merit and intends to vigorously defend against them. The Company and certain Affiliates operate under regulatory authorities that require that they maintain minimum financial or capital requirements. Management is not aware of any significant violations of such requirements. The Company has committed to co-invest in certain investment partnerships. As of December 31, 2015 , these unfunded commitments were $76.8 million and may be called in future periods. In connection with a past acquisition agreement, the Company is contractually entitled to reimbursement from a prior owner for $15.2 million of these commitments if they are called. As of December 31, 2015, Company was contingently liable, upon achievement by certain Affiliates of specified financial targets, to make payments through 2019 of up to $85.6 million associated with its consolidated Affiliates and $166.5 million associated with its equity method Affiliates. The Company expects to make payments of $14.0 million (none in 2016) of the $85.6 million related to consolidated Affiliates and no payments related to the Company’s equity method Affiliates.

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2015
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements The following tables summarize the Company’s financial assets and liabilities that are measured at fair value on a recurring basis: Fair Value Measurements December 31, 2014 Level 1 Level 2 Level 3 Financial Assets Cash equivalents $ 59.1 $ 59.1 $ — $ — Investments in marketable securities (1) Trading securities 22.3 22.3 — — Available-for-sale securities 150.3 150.3 — — Other investments 167.2 13.6 19.4 134.2 Financial Liabilities Contingent payment arrangements (2) $ 59.3 $ — $ — $ 59.3 Obligations to related parties (2) 93.1 — — 93.1 Interest rate swaps 1.4 — 1.4 — Foreign currency forward contracts (3) 0.5 — 0.5 — Fair Value Measurements December 31, 2015 Level 1 Level 2 Level 3 Financial Assets Cash equivalents $ 65.9 $ 65.9 $ — $ — Investments in marketable securities (1) Trading securities 19.4 19.4 — — Available for sale securities 180.5 180.5 — — Other investments 149.3 20.7 2.6 126.0 Financial Liabilities Contingent payment arrangements (2) $ 10.2 $ — $ — $ 10.2 Obligations to related parties (2) 137.3 — — 137.3 __________________________ (1) Principally investments in equity securities. (2) Amounts are presented within Other liabilities. (3) Amounts are presented within Other assets or Other liabilities. The following are descriptions of the significant financial assets and liabilities measured at fair value and the fair value methodologies used. Cash equivalents consist primarily of highly liquid investments in daily redeeming money market funds that are classified as Level 1. Investments in marketable securities consist primarily of investments in publicly traded securities and in funds advised by Affiliates that are valued using net asset value (“NAV”). Publicly traded securities and investments in daily redeeming funds that calculate NAVs are classified as Level 1. Other investments consist primarily of funds advised by Affiliates and are valued using NAV. Investments in daily redeeming funds that calculate NAVs are classified as Level 1. Investments in funds that permit redemptions monthly or quarterly are classified as Level 2. Investments in funds that are subject to longer redemption restrictions are classified as Level 3. The fair value of Level 3 assets is primarily determined using NAV one quarter in arrears (adjusted for current period calls and distributions). Contingent payment arrangements represent the present value of the expected future settlement of contingent payment arrangements related to the Company’s investments in consolidated Affiliates. The significant unobservable inputs that are used in the fair value measurement of these obligations are growth and discount rates. Increases in the growth rate result in a higher obligation while an increase in the discount rate results in a lower obligation. Obligations to related parties include agreements to repurchase Affiliate equity and liabilities, offsetting certain investments that are held by the Company but economically attributable to a related party. The significant unobservable inputs that are used in the fair value measurement of the agreements to repurchase Affiliate equity are growth and discount rates. Increases in the growth rate result in a higher obligation while an increase in the discount rate results in a lower obligation. The liability to a related party is measured based upon certain investments held by the Company, the fair value of which is determined using NAV one quarter in arrears adjusted for current period calls and distributions. Interest rate swaps and foreign currency forward contracts use model-derived valuations in which all significant inputs are observable in active markets to determine the fair value of these derivatives. It is the Company’s policy to value financial assets or liabilities transferred as of the beginning of the period in which the transfer occurs. There were no significant transfers of financial assets or liabilities from Level 1 to Level 2 in 2014 or 2015 . Level 3 Financial Assets and Liabilities The following table presents the changes in Level 3 assets and liabilities: For the Years Ended December 31, 2014 2015 Other Investments Contingent Payment Arrangements Obligations to Related Parties Other Investments Contingent Payment Arrangements Obligations to Related Parties Balance, beginning of period $ 131.8 $ 50.2 $ 76.9 $ 134.2 $ 59.3 $ 93.1 Net gains/losses 11.4 (1) 9.1 (2) 5.5 (3) (5.5 ) (1) (40.9 ) (2) 4.6 (3) Purchases and issuances 17.4 — 96.7 16.3 9.3 164.1 Settlements and reductions (26.4 ) — (86.0 ) (25.5 ) (17.5 ) (124.5 ) Net transfers in and/or out of Level 3 — — — 6.5 — — Balance, end of period $ 134.2 $ 59.3 $ 93.1 $ 126.0 $ 10.2 $ 137.3 Net change in unrealized gains/losses relating to instruments still held at the reporting date $ 17.1 $ 9.1 $ (0.1 ) $ 6.1 $ (40.9 ) $ (7.3 ) __________________________ (1) Gains and losses on Other investments are recorded in Investment and other (income) expense. (2) Accretion and changes to the Company’s contingent payment arrangements are recorded in Imputed interest expense and contingent payment arrangements. (3) Gains and losses associated with agreements to repurchase Affiliate equity are recorded in Imputed interest expense and contingent payment arrangements. Gains and losses related to liabilities offsetting certain investments are recorded in Investment and other (income) expense. The following table presents certain quantitative information about the significant unobservable inputs used in valuing the Company’s Level 3 financial liabilities: Quantitative Information about Level 3 Fair Value Measurements Valuation Techniques Unobservable Input Fair Value at Range at December 31, 2014 Fair Value at Range at December 31, 2015 Contingent payment arrangements Discounted cash flow Growth rates $ 59.3 6% $ 10.2 3% - 8% Discount rates 15% 15% Affiliate equity repurchase obligations Discounted cash flow Growth rates 21.5 5% - 9% 62.3 1% - 9% Discount rates 15% - 16% 14% - 15% Investments in Certain Entities that Calculate Net Asset Value The Company uses the NAV of certain investments as their fair value. The NAVs provided by the investees have been derived from the fair values of the underlying investments as of the measurement dates. The following table summarizes the nature of these investments and any related liquidity restrictions or other factors that may impact the ultimate value realized: December 31, 2014 December 31, 2015 Category of Investment Fair Value Unfunded Commitments Fair Value Unfunded Commitments Private equity (1) $ 134.2 $ 67.8 $ 126.0 $ 76.8 Other funds (2) 75.8 — 72.3 — $ 210.0 $ 67.8 $ 198.3 $ 76.8 __________________________ (1) These funds primarily invest in a broad range of private equity funds and make direct investments. Distributions will be received as the underlying assets are liquidated over the life of the funds, which is generally 15 years . (2) These are multi-disciplinary funds that invest across various asset classes and strategies, including long/short equity, credit and real estate. Investments are generally redeemable on a daily or quarterly basis. Other Financial Assets and Liabilities Not Carried at Fair Value The carrying amount of Cash and cash equivalents, Receivables, and Payables and accrued liabilities approximates fair value because of the short-term nature of these instruments. The carrying value of notes receivable approximates fair value because interest rates and other terms are at market rates. The carrying value of Senior bank debt approximates fair value because the debt has variable interest based on selected short-term rates. The following table summarizes the Company’s other financial liabilities not carried at fair value: December 31, 2014 December 31, 2015 Carrying Amount Fair Value Carrying Amount Fair Value Fair Value Hierarchy Senior notes $ 736.8 $ 786.2 $ 944.6 $ 966.3 Level 2 Convertible securities 303.1 532.1 305.2 483.6 Level 2

Business Combinations

Business Combinations	12 Months Ended
	Dec. 31, 2015
Business Combinations [Abstract]
Business Combinations	Business Combinations The Company completed majority investments in Baker Street Advisors, LLC (“Baker Street”) on April 1, 2015 and myCIO Wealth Partners, L.P. (“myCIO”) on October 1, 2015. The Company’s provisional purchase price allocations were measured using a financial model that includes assumptions of expected market performance, net client flows and discount rates. The associated provisional amounts may be revised upon completion of the final valuation. The consideration paid (less net tangible assets acquired) will be deductible for U.S. tax purposes over a 15 -year life. The purchase price allocation for these investments was as follows: Total Consideration paid $ 76.1 Contingent payment obligations 9.3 Non-controlling interests 33.8 Enterprise value $ 119.2 Acquired client relationships $ 52.5 Tangible assets, net 2.4 Goodwill 64.3 $ 119.2 The excess of the enterprise value over the separately identifiable net assets acquired was recorded as goodwill and the segment allocation was as follows: Total Institutional 14.4 % Mutual Fund — % High Net Worth 85.6 % Unaudited pro-forma financial results are set forth below, assuming these investments occurred on January 1, 2014 and the Company’s structured partnership interests had been in effect for the entire period. For the Years Ended December 31, 2014 (Unaudited) 2015 (Unaudited) Revenue $ 2,538.2 $ 2,499.4 Net income (controlling interest) 454.5 517.9 Earnings per share (basic) 8.26 9.53 Earnings per share (diluted) 8.05 9.31 The unaudited pro-forma financial results are not necessarily indicative of the financial results had the investments been consummated at the beginning of the periods presented, nor are they necessarily indicative of the financial results expected in future periods. The unaudited pro-forma financial results do not include the impact of transaction and integration related costs or benefits that may be expected to result from these investments. The Company’s new investments contributed $15.3 million and $1.3 million to the Company’s Revenue and earnings, respectively, during 2015. The Company had liabilities to related parties for contingent payment arrangements in connection with certain business combinations. The total payable was $59.3 million and $10.2 million as of December 31, 2014 and 2015, respectively, and was included in Other liabilities. The Company made no payments associated with these liabilities in 2014. In 2015, the Company made payments of $17.5 million associated with these liabilities. During 2013, the Company adjusted its estimate of its contingent payment obligations and recognized a loss totaling $10.3 million . During 2014, the Company made no such adjustments. During 2015, the Company adjusted its estimate of its contingent payment obligations and recorded a gain of $44.7 million .

Goodwill and Acquired Client Re

Goodwill and Acquired Client Relationships	12 Months Ended
	Dec. 31, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Acquired Client Relationships	Goodwill and Acquired Client Relationships The following tables present the change in Goodwill and components of Acquired client relationships, net of the Company’s consolidated Affiliates: Goodwill Institutional Mutual Fund High Net Worth Total Balance, as of December 31, 2013 $ 1,076.3 $ 928.1 $ 337.3 $ 2,341.7 Goodwill acquired 97.2 208.1 39.2 344.5 Foreign currency translation (14.4 ) (10.9 ) (8.1 ) (33.4 ) Balance, as of December 31, 2014 $ 1,159.1 $ 1,125.3 $ 368.4 $ 2,652.8 Goodwill acquired 9.2 — 55.1 64.3 Foreign currency translation (27.0 ) (5.8 ) (15.9 ) (48.7 ) Balance, as of December 31, 2015 $ 1,141.3 $ 1,119.5 $ 407.6 $ 2,668.4 Acquired Client Relationships Definite-lived Indefinite-lived Total Gross Book Value Accumulated Amortization Net Book Value Net Book Value Net Book Value Balance, as of December 31, 2013 $ 1,039.5 $ (442.8 ) $ 596.7 $ 864.0 $ 1,460.7 New Investments 220.3 — 220.3 244.7 465.0 Amortization and impairments — (122.2 ) (122.2 ) — (122.2 ) Foreign currency translation (4.7 ) — (4.7 ) (20.4 ) (25.1 ) Balance, as of December 31, 2014 $ 1,255.1 $ (565.0 ) $ 690.1 $ 1,088.3 $ 1,778.4 New Investments 52.5 — 52.5 — 52.5 Amortization and impairments — (115.4 ) (115.4 ) — (115.4 ) Foreign currency translation (5.8 ) — (5.8 ) (23.3 ) (29.1 ) Balance, as of December 31, 2015 $ 1,301.8 $ (680.4 ) $ 621.4 $ 1,065.0 $ 1,686.4 Definite-lived acquired client relationships are amortized over their expected useful lives. As of December 31, 2015 , these relationships were being amortized over a weighted average life of approximately ten years. The Company recognized amortization expense for these relationships of $122.2 million for the year ended December 31, 2014 , as compared to $115.4 million for the year ended December 31, 2015 . Based on relationships existing as of December 31, 2015, the Company estimates that its consolidated annual amortization expense will be $110 million for each of the next five years. During 2014 and 2015, the Company completed impairment assessments on its goodwill and definite-lived and indefinite-lived acquired client relationships and no impairments were indicated.

Equity Method Investments in Af

Equity Method Investments in Affiliates	12 Months Ended
	Dec. 31, 2015
Equity Method Investments and Joint Ventures [Abstract]
Equity Investments in Affiliates	Equity Method Investments in Affiliates The Company completed minority investments in Abax Investments (Pty) Ltd on December 18, 2015 and Ivory Investment Management, L.P. on December 31, 2015 for approximately $200 million . The Company’s provisional purchase price allocations were measured using a financial model that includes assumptions of expected market performance, net client flows and discount rates. The associated provisional amounts may be revised upon completion of the final valuation. The consideration paid (less net tangible assets acquired) will be deductible for U.S. tax purposes over a 15 -year life. Also during 2015, the Company paid $23.3 million related to a contingent payment obligation. A portion of the purchase price attributable to the Company’s equity method Affiliates relates to definite-lived acquired client relationships. As of December 31, 2015 , the definite-lived acquired relationships were being amortized over a weighted average life of approximately fourteen years. The Company recognized amortization expense for these relationships of $32.3 million for the year ended December 31, 2014 , as compared to $34.3 million for the year ended December 31, 2015 . Based on relationships existing as of December 31, 2015, the Company estimates the annual amortization expense attributable to its current equity-method Affiliates to be $37 million for each of the next five years. The following table presents summarized financial information for Affiliates accounted for under the equity method. For the Years Ended December 31, 2013 2014 2015 Revenue (1) $ 1,589.6 $ 1,869.3 $ 2,217.1 Net income 1,321.9 253.8 431.5 December 31, 2014 2015 Assets (2) $ 34,729.2 $ 30,663.4 Liabilities and Non-controlling interest (2) 33,048.6 29,434.7 __________________________ (1) Revenue includes advisory fees for asset management services and net investment income from consolidated investment partnerships. (2) Assets consist primarily of investment securities in consolidated investment partnerships, which are generally held by non-controlling interests. The Company’s share of undistributed earnings from equity method investments totaled $101.5 million as of December 31, 2015 . Subsequent to year end, the Company completed minority investments in Systematica Investments L.P. and Baring Private Equity Asia on January 4, 2016 for approximately $550 million .

Fixed Assets and Lease Commitme

Fixed Assets and Lease Commitments	12 Months Ended
	Dec. 31, 2015
Fixed Assets and Lease Commitments [Abstract]
Fixed Assets and Lease Commitments	Fixed Assets and Lease Commitments Fixed assets consisted of the following: December 31, 2014 2015 Building and leasehold improvements $ 84.1 $ 104.7 Software 40.8 45.4 Equipment 38.3 39.9 Furniture and fixtures 17.5 22.4 Land, improvements and other 18.7 18.6 Fixed assets, at cost 199.4 231.0 Accumulated depreciation and amortization (104.0 ) (116.9 ) Fixed assets, net $ 95.4 $ 114.1 The Company and its Affiliates lease office space and equipment for their operations. At December 31, 2015 , the Company’s aggregate future minimum payments for operating leases having initial or non-cancelable lease terms greater than one year were payable as follows: Required Minimum Payments (1) 2016 $ 36.0 2017 33.7 2018 31.0 2019 29.5 2020 28.4 Thereafter 82.1 __________________________ (1) The controlling interest portion is $10.7 million through 2016, $11.0 million each in 2017 and in 2018, $10.6 million in 2019, $10.1 million in 2020 and $38.7 million thereafter. Consolidated rent expense for 2013 , 2014 and 2015 was $30.3 million , $30.5 million and $36.3 million , respectively.

Payables and Accrued Liabilitie

Payables and Accrued Liabilities	12 Months Ended
	Dec. 31, 2015
Payables and Accruals [Abstract]
Payables and Accrued Liabilities	Payables and Accrued Liabilities Payables and accrued liabilities consisted of the following: December 31, 2014 2015 Accrued compensation and distributions $ 491.3 $ 455.0 Unsettled fund share payables 78.3 76.6 Accrued income taxes 59.8 67.9 Accrued share repurchases 47.8 — Accrued professional fees 26.9 31.4 Other 104.2 98.5 $ 808.3 $ 729.4

Related Party Transactions

Related Party Transactions	12 Months Ended
	Dec. 31, 2015
Related Party Transactions [Abstract]
Related Party Transactions	Related Party Transactions The Company has reflected a prior owner’s investments in certain private equity investment partnerships sponsored by an Affiliate and recorded on the Company’s Consolidated Balance Sheet as either a liability in Other liabilities or as a Non-controlling interest, depending on the structure of the prior owner’s investments in the partnerships. The total liability was $71.6 million and $75.0 million at December 31, 2014 and 2015, respectively. The total non-controlling interest was $13.5 million and $5.1 million at December 31, 2014 and 2015, respectively. In certain cases, Affiliate management owners and Company officers may serve as trustees or directors of certain mutual funds from which the Affiliate earns advisory fee revenue. See Note 20 for information on transactions in Affiliate equity.

Stockholders' Equity

Stockholders' Equity	12 Months Ended
	Dec. 31, 2015
Stockholders' Equity Note [Abstract]
Stockholders' Equity	Stockholders’ Equity Preferred Stock The Company is authorized to issue up to 5.0 million shares of Preferred Stock. Any such Preferred Stock issued by the Company may rank prior to common stock as to dividend rights, liquidation preference or both, may have full or limited voting rights and may be convertible into shares of common stock. Common Stock The Company is authorized to issue up to 150.0 million shares of Voting Common Stock and 3.0 million shares of Class B Non-Voting Common Stock. As more fully described in Note 8, the Company is party to a forward equity sale agreement under which the Company may sell shares of its common stock. The Company’s Board of Directors has periodically authorized share repurchase programs, most recently in May 2015, authorizing the Company to repurchase up to 3.0 million shares of its common stock. As of December 31, 2015, there were 2.3 million remaining shares available for repurchase under the May 2015 program, which does not expire. The timing and amount of issuances and repurchases will be determined at the discretion of the Company’s management. The following is a summary of the Company’s recent share repurchase activity: Period Shares Repurchased Average Price 2013 0.1 $ 184.89 2014 1.2 204.72 2015 1.7 209.39 Financial Instruments The Company’s junior convertible securities contain an embedded right for holders to receive shares of the Company’s common stock under certain conditions. These arrangements, as well as the forward equity sale agreement, meet the definition of equity and are not required to be accounted for separately as derivative instruments.

Share-Based Compensation

Share-Based Compensation	12 Months Ended
	Dec. 31, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Share-Based Compensation	Share-Based Compensation Share-Based Incentive Plans The Company has established various plans under which it is authorized to grant restricted stock, restricted stock units, stock options and stock appreciation rights. Compensation payable under these plans is intended to qualify as performance-based compensation within the meaning of Section 162(m) of the Internal Revenue Code. The Company may also grant cash awards that can be notionally invested in one or more specified measurement funds, including the Company’s common stock. Share-Based Incentive Compensation The following is a summary of share-based compensation expense: Period Share-Based Compensation Expense Tax Benefit 2013 $ 27.5 $ 10.6 2014 29.3 11.3 2015 34.2 13.2 The cash received for options exercised was $41.4 million and $57.8 million during the years ended December 31, 2014 and 2015 , respectively. The actual tax benefit recognized from share-based incentive plans was $60.2 million and $44.5 million during the years ended December 31, 2014 and 2015, respectively. The excess tax benefit classified as a financing cash flow was $61.5 million , and $44.5 million during the years ended December 31, 2014 and 2015 , respectively. There was $56.8 million and $70.6 million of unrecognized compensation expense related to share-based compensation arrangements as of December 31, 2014 and 2015 , respectively. The unrecognized compensation expense at December 31, 2015 will be recognized over a weighted average period of approximately three years (assuming no forfeitures). Stock Options The following table summarizes the transactions of the Company’s stock options: Stock Options Weighted Average Exercise Price Weighted Average Remaining Contractual Life (years) Unexercised options outstanding—January 1, 2015 2.3 $ 83.42 Options granted 0.0 207.61 Options exercised (0.9 ) 65.95 Options forfeited (0.0 ) 101.29 Unexercised options outstanding—December 31, 2015 1.4 96.18 2.2 Exercisable at December 31, 2015 1.3 94.43 2.1 The Company granted stock options with fair values of $1.0 million , $0.6 million , and $1.0 million in 2013 , 2014 and 2015 , respectively. Stock options generally vest over a period of three to five years and expire seven to ten years after the grant date. All options have been granted with exercise prices equal to the fair market value of the Company’s common stock on the date of grant. The Company generally uses treasury stock to settle stock option exercises. The total intrinsic value of options exercised during the years ended December 31, 2013 , 2014 and 2015 was $77.4 million , $92.6 million and $130.2 million , respectively. As of December 31, 2015 , the intrinsic value of exercisable options outstanding was $89.0 million and 3.5 million options are available for future grant under the Company’s option plans. The fair value of options granted was estimated using the Black-Scholes option pricing model. The weighted average fair value of options granted during the years ended December 31, 2013 , 2014 and 2015 was $61.82 , $60.20 , and $54.92 per option, respectively, based on the weighted-average grant date assumptions stated below. For the Years Ended December 31, 2013 2014 2015 Dividend yield 0.0 % 0.0 % 0.0 % Expected volatility (1) 34.4 % 29.7 % 26.7 % Risk-free interest rate (2) 1.5 % 1.8 % 1.5 % Expected life of options (in years) (3) 5.0 5.0 5.0 Forfeiture rate (3) 0.0 % 0.0 % 0.0 % __________________________ (1) Expected volatility is based on historical and implied volatility. (2) Risk-free interest rate is based on the U.S. Treasury yield curve in effect at the date of grant. (3) Expected life of options (in years) is based on the Company’s historical data and expected exercise behavior. Restricted Stock The following table summarizes the transactions of the Company’s restricted stock: Restricted Stock Weighted Average Grant Date Value Unvested units—January 1, 2015 0.4 $ 182.83 Units granted 0.3 197.59 Units vested (0.1 ) 174.19 Units forfeited (0.0 ) 190.23 Unvested units—December 31, 2015 0.6 192.04 The Company granted awards with fair values of $53.5 million , $8.0 million , and $50.7 million in 2013 , 2014 and 2015 , respectively. These awards were valued based on the closing price of the Company’s common stock on the date of grant and contain vesting conditions requiring service over a period of three to eight years. In certain circumstances, awards also require certain performance conditions to be satisfied and the Company may elect to settle the awards in shares of the Company’s common stock or cash. In 2013, the Company granted 0.1 million awards that vest when a required service period has been completed and if certain market conditions are satisfied. The market conditions require separate 15% , 25% and 35% increases in the price of the Company’s common stock to be achieved during the six -year term of the awards; however, shares underlying the awards are eligible to be delivered, assuming the service conditions have been satisfied, only on the fourth , fifth and sixth anniversaries of the grant date if the 15% market condition has been maintained. The awards were valued using a Monte Carlo simulation with grant date assumptions for expected volatility (31.6%) , risk-free interest rate (2.0%) and dividend yield ( 0.0% ). The fair value of the awards will be recognized as compensation over a service period of four years, which is the longer of the explicit service period or the period the market condition is expected to be met. As of December 31, 2015 , the Company had 1.5 million shares available for grant under its plans.

Affiliate Equity

Affiliate Equity	12 Months Ended
	Dec. 31, 2015
Affiliate Equity
Affiliate Equity	Affiliate Equity Affiliate equity interests provide holders with a ratable portion of ownership in one of the Company’s Affiliates. Affiliate equity interests are allocated income in a manner that is consistent with the structured partnership interests in place at the respective Affiliate. When the Company owns a share of the Affiliate’s revenue without regard to expenses, Affiliate equity holders are allocated Owner’s Allocation in proportion to their respective ownership interests. When the Company owns a share of the Affiliate’s revenue less certain agreed-upon expenses, Affiliate equity holders are allocated their share of revenue net of the agreed categories of expenses. The Company’s Affiliates generally pay quarterly distributions to Affiliate equity holders. Distributions paid to Affiliate equity holders were $267.1 million , $569.4 million and $431.4 million for the years ended December 31, 2013, 2014 and 2015, respectively. Affiliate equity interests provide the Company a conditional right to call (on an annual basis following an Affiliate equity holder’s departure) and Affiliate equity holders have a conditional right to put their interests at certain intervals (between five and fifteen years from the date the equity interest is received or on an annual basis following an Affiliate equity holder’s departure). Affiliate equity holders are also permitted to sell their equity interests to other individuals or entities in certain cases, subject to the Company's approval or other restrictions. The purchase price of these conditional purchases are generally calculated based upon a multiple of cash flow distributions, which is intended to represent fair value. The Company, at its option, may pay for Affiliate equity purchases in cash, shares of its common stock or other forms of consideration and can consent to the transfer of these interests to other individuals or entities. Sales and repurchases of Affiliate equity generally occur at fair value; however, the Company also grants Affiliate equity to its Affiliate partners, employees and officers as a form of compensation. If the equity is issued for consideration below the fair value of the equity or repurchased for consideration above the fair value of the equity, then such difference is recorded as compensation expense over the requisite service period. The following is a summary of Affiliate equity expense: 2013 2014 2015 Controlling interest $ 56.4 $ 47.4 $ 16.9 Tax benefit (21.7 ) (18.2 ) (6.5 ) Controlling interest, net $ 34.7 $ 29.2 $ 10.4 Non-controlling interest 15.9 37.0 51.6 Total $ 50.6 $ 66.2 $ 62.0 The following is a summary of unrecognized Affiliate equity expense: Unrecognized Affiliate Equity Expense Period Controlling Interest Remaining Life Non-Controlling Interest Remaining Life 2013 $ 36.1 3 years $ 32.1 7 years 2014 29.5 3 years 41.6 6 years 2015 22.4 3 years 51.9 5 years The Company periodically issues Affiliate equity interests to and repurchases Affiliate equity interests from its Affiliate partners. The amount paid for repurchases was $36.9 million , $32.6 million and $130.8 million for the years ended December 31, 2013, 2014 and 2015, respectively. The total amount received for issuances was $2.5 million , $11.0 million and $6.1 million for the years ended December 31, 2013, 2014 and 2015, respectively. The Company records amounts receivable and payable to Affiliate partners in connection with the transfer of Affiliate equity interests that have not settled at the end of the period. The total receivable was $20.8 million and $22.6 million at December 31, 2014 and 2015 , respectively, and was included in Other assets. The total payable was $29.3 million and $62.3 million as of December 31, 2014 and 2015 , respectively, and was included in Other liabilities. The total amount received for such receivables was $6.9 million , $9.7 million and $7.4 million for the years ended December 31, 2013, 2014 and 2015, respectively. The total amount paid for such liabilities was $5.5 million , $4.4 million and $17.2 million for the years ended December 31, 2013, 2014 and 2015, respectively. The current redemption value of the Company’s Affiliate equity has been presented as Redeemable non-controlling interests on the Company’s Consolidated Balance Sheets. Changes in the current redemption value are recorded to Additional paid-in capital. The following table presents the changes in Redeemable non-controlling interests: 2014 2015 Balance, as of January 1 $ 641.9 $ 645.5 Repurchases of redeemable Affiliate equity (61.7 ) (161.3 ) Transfers from Non-controlling interests 22.7 49.5 Changes in redemption value 43.0 81.6 Decrease attributable to consolidated products (0.4 ) (2.8 ) Balance, as of December 31 $ 645.5 $ 612.5 During the years ended 2013 , 2014 and 2015 , the Company acquired interests from, and transferred interests to, holders of Affiliate equity. The following schedule discloses the effect of changes in the Company’s ownership interests in its Affiliates on the controlling interest’s equity: For the Years Ended December 31, 2013 2014 2015 Net income (controlling interest) $ 360.5 $ 452.1 $ 516.0 Increase in controlling interest paid-in capital related to Affiliate equity issuances 13.1 2.5 0.7 Decrease in controlling interest paid-in capital related to Affiliate equity repurchases (87.1 ) (35.8 ) (89.8 ) Net income attributable to controlling interest and transfers (to) or from Non-controlling interests $ 286.5 $ 418.8 $ 426.9

Benefit Plans

Benefit Plans	12 Months Ended
	Dec. 31, 2015
Compensation and Retirement Disclosure [Abstract]
Benefit Plans	Benefit Plans The Company has three defined contribution plans consisting of a qualified employee profit-sharing plan covering substantially all of its full-time employees and several of its Affiliates, and non-qualified plans for certain senior employees. AMG’s other Affiliates generally have separate defined contribution retirement plans. Under each of the qualified plans, AMG and each participating Affiliate, as the case may be, are able to make discretionary contributions for the benefit of qualified plan participants up to Internal Revenue Service limits. The Company has a Deferred Compensation Plan that provides officers and directors of the Company the opportunity to voluntarily defer base salary, bonus payments and director fees, as applicable, on a pre-tax basis, and invest such deferred amounts in one or more specified measurement funds. While the Company has no obligation to do so, the Deferred Compensation Plan also provides the Company the opportunity to make discretionary contributions; in the event any such contributions are made, contributed amounts will be subject to vesting and forfeiture provisions. Consolidated expenses related to the Company’s benefit plans in 2013 , 2014 and 2015 were $14.1 million , $17.2 million and $18.7 million , respectively.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The consolidated income tax provision included taxes attributable to the controlling interest and, to a lesser extent, taxes attributable to non-controlling interests follows: For the Years Ended December 31, 2013 2014 2015 Controlling Interests: Current tax $ 153.1 $ 149.8 $ 152.4 Intangible-related deferred taxes 38.1 47.8 77.7 Other deferred taxes (6.2 ) 15.8 21.2 Total controlling interests 185.0 213.4 251.3 Non-controlling Interests: Current tax $ 13.3 $ 15.3 $ 9.8 Deferred taxes (4.2 ) (0.8 ) (4.2 ) Total non-controlling interests 9.1 14.5 5.6 Provision for income taxes $ 194.1 $ 227.9 $ 256.9 Income before income taxes (controlling interest) $ 545.5 $ 665.5 $ 767.3 Effective tax rate attributable to controlling interests (1) 33.9 % 32.1 % 32.8 % __________________________ (1) Taxes attributable to the controlling interest divided by Income before income taxes (controlling interest). A summary of the consolidated provision for income taxes follows: For the Years Ended December 31, 2013 2014 2015 Current: Federal $ 104.1 $ 93.8 $ 106.3 State 21.1 27.1 18.3 Foreign 41.2 44.2 37.6 Total current 166.4 165.1 162.2 Deferred: Federal 38.1 72.5 97.9 State 8.9 1.1 14.2 Foreign (19.3 ) (10.8 ) (17.4 ) Total deferred 27.7 62.8 94.7 Provision for income taxes $ 194.1 $ 227.9 $ 256.9 The components of income before income taxes consisted of the following: For the Years Ended December 31, 2013 2014 2015 Domestic $ 604.0 $ 784.1 $ 827.6 International 259.7 229.5 263.0 $ 863.7 $ 1,013.6 $ 1,090.6 The Company’s effective income tax rate differed from the amount computed by using income before income taxes and applying the U.S. federal income tax rate because of the effect of the following items: For the Years Ended December 31, 2013 2014 2015 Tax at U.S. federal income tax rate 35.0 % 35.0 % 35.0 % State income taxes, net of federal benefit (1) 2.8 2.1 2.6 Effect of foreign operations (2.5 ) (5.3 ) (3.5 ) Other (1.4 ) 0.3 (1.3 ) Effective tax rate (controlling interest) 33.9 32.1 32.8 Effect of income from non-controlling interests (11.4 ) (9.6 ) (9.2 ) Effect tax rate 22.5 % 22.5 % 23.6 % __________________________ (1) State income taxes included changes related to state valuation allowances. In 2013, the Company realized deferred tax benefits of $7.2 million on investments in foreign subsidiaries deemed permanent in duration (including $5.9 million for subsidiaries that became permanent in duration in 2013) and $11.2 million ( $7.6 million to the controlling interest) from the revaluation of its deferred taxes resulting from a reduction in corporate tax rates in the United Kingdom. In 2014, the Company realized deferred tax benefits of $30.3 million on investments in foreign subsidiaries deemed permanent in duration (including $24.5 million for subsidiaries that became permanent in duration in 2014) and reduced its valuation allowance $6.5 million for state net operating loss carryforwards. In 2015, the Company realized $17.1 million of tax benefits from investments in foreign subsidiaries deemed permanent in duration and $5.0 million from its indefinite reinvestment of certain 2015 foreign earnings. In 2015, the Company also realized $10.0 million ( $6.5 million to the controlling interest) of deferred tax benefits resulting from a reduction in corporate tax rates in the United Kingdom. The Company did not provide for deferred taxes on the excess of the financial reporting basis over the tax basis in its investments in foreign subsidiaries that were permanent in duration. This amount becomes taxable upon a repatriation of assets from a sale or liquidation of the subsidiary. As of December 31, 2015 , the amount of such difference was $188.1 million . The deferred taxes not recognized at December 31, 2015 for this difference were $71.1 million . The components of deferred tax assets and liabilities were as follows: December 31, 2014 2015 Deferred Tax Assets Deferred compensation $ 26.8 $ 30.5 State net operating loss carryforwards 15.2 17.1 Tax benefit of uncertain tax positions 16.0 14.6 Accrued expenses 19.6 4.4 Foreign loss carryforwards 11.5 12.3 Other 1.4 — Total deferred tax assets 90.5 78.9 Valuation allowance (18.4 ) (20.5 ) Deferred tax assets, net of valuation allowance $ 72.1 $ 58.4 Deferred Tax Liabilities Intangible asset amortization $ (270.9 ) $ (320.2 ) Non-deductible intangible amortization (126.4 ) (109.8 ) Convertible securities interest (92.5 ) (99.8 ) Deferred income (74.0 ) (92.8 ) Other — (1.5 ) Total deferred tax liabilities (563.8 ) (624.1 ) Net deferred tax liability $ (491.7 ) $ (565.7 ) Deferred tax liabilities were primarily the result of tax deductions for the Company’s intangible assets and convertible securities. The Company amortizes most of its intangible assets for tax purposes only, reducing its tax basis below its carrying value for financial statement purposes and generating deferred taxes each reporting period. The Company’s convertible securities also generate deferred taxes because the Company’s tax deductions are higher than the interest expense recorded for financial statement purposes. At December 31, 2015 , the Company had state net operating loss carryforwards that expire over a 19 -year period and foreign loss carryforwards that expire over a 20 -year period. The Company had established a valuation allowance to offset a portion of these carryforwards because of the uncertainty of realizing their full value. In 2014, the Company reduced its valuation allowance $15.7 million on state loss carryforwards from improved projections of taxable income, and increased state uncertain tax positions by $9.2 million for a net $6.5 million state tax benefit. In 2014, the Company also reduced its valuation allowance on loss carryforwards by $2.5 million . In 2015, the Company increased its valuation allowance $2.1 million , principally for loss carryforwards deemed unrealizable. The Company had uncertain tax positions of $20.4 million , $28.8 million and $26.9 million as of December 31, 2013 , 2014 and 2015 , respectively. These amounts included $1.7 million , $1.6 million and $1.8 million of interest and related charges, respectively. At December 31, 2013 , 2014 and 2015 , these liabilities also included $17.2 million , $26.4 million and $25.3 million , respectively, for tax positions that, if recognized, would affect the Company’s effective tax rate. A reconciliation of the beginning and ending amount of unrecognized tax benefits follows: For the Years Ended December 31, 2013 2014 2015 Balance, as of January 1 $ 22.6 $ 20.4 $ 28.8 Additions based on current year tax positions 4.1 2.6 2.2 Additions based on prior years’ tax positions — 10.8 1.6 Reductions for prior years’ tax provisions (0.1 ) — — Reductions related to lapses of statutes of limitations (5.4 ) (4.1 ) (4.3 ) Additions (reductions) related to foreign exchange rates (0.8 ) (0.9 ) (1.4 ) Balance, as of December 31 $ 20.4 $ 28.8 $ 26.9 During 2014, uncertain tax positions increased $8.4 million , principally for the uncertain nature of several of its state net operating loss carryforwards. During 2015, uncertain tax positions decreased $1.9 million , principally from changes in foreign exchange rates. The Company does not anticipate that uncertain tax positions will change significantly over the next twelve months. The Company periodically has tax examinations in the U.S. and foreign jurisdictions. Examination outcomes, and any related settlements, are subject to significant uncertainty. The completion of examinations may result in the payment of additional taxes and/or the recognition of tax benefits. The Company was generally no longer subject to income tax examinations by any tax authorities for years before 2010.

Earnings Per Share

Earnings Per Share	12 Months Ended
	Dec. 31, 2015
Earnings Per Share [Abstract]
Earnings Per Share	Earnings Per Share The following is a reconciliation of the numerator and denominator used in the calculation of basic and diluted earnings per share available to common stockholders. For the Years Ended December 31, 2013 2014 2015 Numerator Net income (controlling interest) $ 360.5 $ 452.1 $ 516.0 Interest expense on convertible securities, net of taxes 10.5 15.2 15.3 Net income (controlling interest), as adjusted $ 371.0 $ 467.3 $ 531.3 Denominator Average shares outstanding (basic) 53.1 55.0 54.3 Effect of dilutive instruments: Stock options and other awards 1.3 1.2 0.7 Forward sale 0.3 0.0 — Junior convertible securities 2.0 2.2 2.2 Average shares outstanding (diluted) 56.7 58.4 57.2 During the years ended December 31, 2013 , 2014 and 2015 , the Company repurchased 0.1 million , 1.2 million and 1.7 million shares of common stock, respectively, at an average share price of $184.89 , $204.72 and $209.39 , respectively, under the share repurchase programs approved by the Company’s Board of Directors. The diluted earnings per share calculations in the table above excluded the anti-dilutive effect of the following shares: For the Years Ended December 31, 2013 2014 2015 Stock options and other awards 0.1 0.0 0.0 Senior convertible securities 2.1 — — Junior convertible securities 2.2 0.4 — As discussed further in Note 20, the Company may settle portions of its Affiliate equity purchases in shares of its common stock. Because it is the Company’s intent to settle these potential repurchases in cash, the calculation of diluted earnings per share excluded any potential dilutive effect from possible share settlements.

Comprehensive Income

Comprehensive Income	12 Months Ended
	Dec. 31, 2015
Stockholders' Equity Note [Abstract]
Comprehensive Income	Comprehensive Income The following tables show the tax effects allocated to each component of Other comprehensive income: For the Year Ended December 31, 2013 Pre-Tax Tax Benefit (Expense) Net of Tax Foreign currency translation gain (loss) $ (19.6 ) $ — $ (19.6 ) Change in net realized and unrealized gain (loss) on derivative securities 1.5 (0.5 ) 1.0 Change in net unrealized gain (loss) on investment securities 19.5 (8.0 ) 11.5 Other comprehensive income (loss) $ 1.4 $ (8.5 ) $ (7.1 ) For the Year Ended December 31, 2014 Pre-Tax Tax Benefit (Expense) Net of Tax Foreign currency translation gain (loss) $ (62.0 ) $ — $ (62.0 ) Change in net realized and unrealized gain (loss) on derivative securities 0.6 (0.3 ) 0.3 Change in net unrealized gain (loss) on investment securities 5.6 (2.2 ) 3.4 Other comprehensive income (loss) $ (55.8 ) $ (2.5 ) $ (58.3 ) For the Year Ended December 31, 2015 Pre-Tax Tax Benefit (Expense) Net of Tax Foreign currency translation gain (loss) $ (93.2 ) $ — $ (93.2 ) Change in net realized and unrealized gain (loss) on derivative securities 2.3 (0.4 ) 1.9 Change in net unrealized gain (loss) on investment securities 34.8 (12.7 ) 22.1 Other comprehensive income (loss) $ (56.1 ) $ (13.1 ) $ (69.2 ) The components of accumulated other comprehensive income (loss), net of taxes, were as follows: Foreign Currency Translation Adjustment Realized and Unrealized Losses on Derivative Securities Unrealized Gain (Loss) on Investment Securities (1) Total Balance, as of December 31, 2013 $ 56.6 $ (1.9 ) $ 19.5 $ 74.2 Other comprehensive income (loss) before reclassifications (62.0 ) 0.3 1.3 (60.4 ) Amounts reclassified from other comprehensive income — 0.0 2.1 2.1 Net other comprehensive income (loss) (62.0 ) 0.3 3.4 (58.3 ) Balance, as of December 31, 2014 $ (5.4 ) $ (1.6 ) $ 22.9 $ 15.9 Other comprehensive income (loss) before reclassifications (93.2 ) 0.8 13.5 (78.9 ) Amounts reclassified from other comprehensive income — 1.1 8.6 9.7 Net other comprehensive income (loss) (93.2 ) 1.9 22.1 (69.2 ) Balance, as of December 31, 2015 $ (98.6 ) $ 0.3 $ 45.0 $ (53.3 ) __________________________ (1) See Note 2 for amounts reclassified from Other comprehensive income.

Selected Quarterly Financial Da

Selected Quarterly Financial Data (Unaudited)	12 Months Ended
	Dec. 31, 2015
Quarterly Financial Information Disclosure [Abstract]
Selected Quarterly Financial Data (Unaudited)	Selected Quarterly Financial Data (Unaudited) The following is a summary of the quarterly results of operations of the Company for the years ended December 31, 2014 and 2015 . 2014 First Quarter Second Quarter Third Quarter Fourth Quarter Revenue $ 593.1 $ 636.3 $ 640.3 $ 641.2 Operating income 193.9 198.4 224.2 198.7 Income before income taxes 208.2 239.1 253.4 312.8 Net income (controlling interest) 77.2 99.1 103.2 172.6 Earnings per share (diluted) 1.40 1.75 1.82 3.02 2015 First Quarter Second Quarter Third Quarter Fourth Quarter Revenue $ 635.0 $ 646.6 $ 613.1 $ 589.8 Operating income 231.4 195.2 215.2 193.2 Income before income taxes 290.3 262.0 249.1 289.2 Net income (controlling interest) 128.0 128.7 109.0 150.3 Earnings per share (diluted) 2.27 2.31 1.98 2.72

Segment Information

Segment Information	12 Months Ended
	Dec. 31, 2015
Segment Reporting [Abstract]
Segment Information	Segment Information Management has assessed and determined that the Company operates in three business segments representing the Company’s three principal distribution channels: Institutional, Mutual Fund and High Net Worth, each of which has different client relationships. The following table summarizes the Company’s financial results for each of the distribution channels: Statements of Income As of and for the Year Ended December 31, 2013 Institutional Mutual Fund High Net Worth Total Revenue $ 948.7 $ 1,023.0 $ 217.1 $ 2,188.8 Net income (controlling interest) 219.9 103.4 37.2 360.5 Total assets 3,196.5 2,448.4 673.9 6,318.8 Goodwill 1,076.3 928.1 337.3 2,341.7 Equity method investments in Affiliates 942.6 77.7 103.0 1,123.3 As of and for the Year Ended December 31, 2014 Institutional Mutual Fund High Net Worth Total Revenue $ 1,022.8 $ 1,242.6 $ 245.5 $ 2,510.9 Net income (controlling interest) 227.0 180.1 45.0 452.1 Total assets 3,739.8 3,082.0 876.3 7,698.1 Goodwill 1,159.1 1,125.3 368.4 2,652.8 Equity method investments in Affiliates 1,533.8 150.3 99.4 1,783.5 As of and for the Year Ended December 31, 2015 Institutional Mutual Fund High Net Worth Total Revenue $ 979.4 $ 1,238.2 $ 266.9 $ 2,484.5 Net income (controlling interest) 229.3 229.7 57.0 516.0 Total assets 3,725.9 3,075.5 983.4 7,784.8 Goodwill 1,141.3 1,119.5 407.6 2,668.4 Equity method investments in Affiliates 1,609.3 185.7 142.1 1,937.1 In 2013 , 2014 and 2015 , revenue attributable to clients domiciled outside the U.S. was approximately 38% , 37% and 40% of total revenue, respectively.

Schedule II Valuation and Quali

Schedule II Valuation and Qualifying Accounts	12 Months Ended
	Dec. 31, 2015
Valuation and Qualifying Accounts [Abstract]
Schedule II Valuation and Qualifying Accounts	Schedule II Valuation and Qualifying Accounts (in millions) Balance Beginning of Period Additions Charged to Costs and Expenses Additions Charged to Other Accounts Deductions Balance End of Period Income Tax Valuation Allowance Year Ending December 31, 2015 $ 18.4 $ 2.1 $ — $ — $ 20.5 2014 36.6 — — 18.2 18.4 2013 21.3 16.9 — 1.6 36.6 Other Allowances (1) Year Ending December 31, 2015 $ 12.1 $ 0.7 $ — $ 2.2 $ 10.6 2014 8.8 4.7 — 1.4 12.1 2013 8.4 2.8 — 2.4 8.8 __________________________ (1) Other Allowances represented reserves on notes received in connection with transfers of our interests in certain Affiliates as well as other receivable amounts, which we considered uncollectible.

Business and Summary of Signi35

Business and Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2015
Accounting Policies [Abstract]
Basis of Presentation and Use of Estimates	Basis of Presentation and Use of Estimates The financial statements are prepared in accordance with accounting principles generally accepted in the U.S. (“GAAP”). All dollar amounts, except per share data in the text and tables herein, are stated in millions unless otherwise indicated. Certain reclassifications have been made to prior years’ financial statements to conform to the current year’s presentation.
Use of Estimates	The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts and disclosures in the financial statements. Actual results could differ from those estimates.
Principles of Consolidation	Principles of Consolidation Investments in Affiliates The Company evaluates the risk, rewards, and significant terms of each of its Affiliate and other investments to determine the appropriate method of accounting. Majority-owned or otherwise controlled investments are consolidated and all material intercompany balances and transactions are eliminated. For its consolidated Affiliates, the portion of the Owners’ Allocation allocated to Affiliate management is included in Net income (non-controlling interests) in the Consolidated Statements of Income. Non-controlling interests on the Consolidated Balance Sheets include capital and undistributed Operating and Owners’ Allocation owned by Affiliate management of the consolidated Affiliates. The effect of any changes in the Company’s equity interests in its consolidated Affiliates resulting from the issuance or repurchase of an Affiliate’s equity by the Company or one of its Affiliates is included as a component of stockholders’ equity, net of the related income tax effect in the period of the change. The current redemption value of non-controlling interests has been presented as Redeemable non-controlling interests on the Consolidated Balance Sheets. AMG applies the equity method of accounting to investments where AMG does not hold a controlling equity interest but has the ability to exercise significant influence over operating and financial matters. In cases where AMG applies the equity method of accounting, it does not typically have an obligation to repurchase Affiliate equity interests. Other investments in which AMG owns less than a 20% interest and does not exercise significant influence are accounted for under the cost method. Under the cost method, income is recognized as dividends when, and if, declared. Affiliate-sponsored Investment Vehicles The Company’s Affiliates sponsor various investment vehicles where they also act as the investment advisor. Certain of these investment vehicles are variable interest entities (“VIEs”) while others are voting rights entities (“VREs”). VIEs are consolidated if the Affiliate is determined to be the primary beneficiary (i.e., if it absorbs a majority of the expected losses, or receives a majority of the expected residual returns). In determining whether the Affiliate is the primary beneficiary, both qualitative and quantitative factors (e.g., the voting rights of the equity holders, economic participation of all parties, including how fees are earned and paid, related party ownership, guarantees and implied relationships) are considered. VREs are consolidated if the Affiliate is the managing member or general partner of the investment vehicle unless unaffiliated investors have certain rights to remove the Affiliate from such role, have substantive participating rights or otherwise control the investment vehicle.
Cash and Cash Equivalents	Cash and Cash Equivalents The Company considers all highly liquid investments, including money market mutual funds, with original maturities of three months or less to be cash equivalents. Cash equivalents are stated at cost, which approximates market value due to the short-term maturity of these investments.
Receivables	Receivables The Company’s Affiliates earn advisory and performance fees, which are billed based on the terms of the related contracts. Billed but uncollected advisory and performance fees are presented within Receivables on the Consolidated Balance Sheets and are generally short-term in nature. Certain of the Company’s Affiliates in the United Kingdom act as an intermediary between clients and their sponsored funds. Normal settlement periods on transactions initiated by these clients result in unsettled fund share receivables and payables that are presented on a gross basis within Receivables and Payables and accrued liabilities on the Consolidated Balance Sheets. The gross presentation of these receivables and offsetting payables reflects the legal relationship between the underlying investor and the Company’s Affiliates.
Investments in Marketable Securities	Investments in Marketable Securities Investments in marketable securities are classified as either trading or available-for-sale and carried at fair value. Unrealized gains or losses on investments classified as available-for-sale are reported, net of tax, as a separate component of Accumulated other comprehensive income in Equity until realized when they are reported in Investment and other (income) expense. Realized and unrealized gains or losses related to trading securities are reported within Investment and other (income) expense in the period they occur on a specific identification basis. If a decline in the fair value of an available-for-sale investment is determined to be other than temporary, the carrying amount of the asset is reduced to its fair value, and the difference is charged to income in the period incurred.
Fair Value Measurements	Fair Value Measurements The Company determines the fair value of certain investment securities and other financial and non-financial assets and liabilities. Fair value is determined based on the price that would be received for an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date, utilizing a hierarchy of three different valuation techniques: Level 1 - Unadjusted quoted market prices for identical instruments in active markets; Level 2 - Quoted prices for similar instruments in active markets; quoted prices for identical or similar instruments in markets that are not active; and model-derived valuations whose inputs, or significant value drivers, are observable; and Level 3 - Prices reflect the Company’s own assumptions concerning unobservable inputs to the valuation model. These inputs require significant management judgment and reflect the Company’s assumptions that market participants would use in pricing the asset or liability.
Fixed Assets	Fixed Assets Fixed assets are recorded at cost and depreciated using the straight-line method over their estimated useful lives. The estimated useful lives of office equipment and furniture and fixtures range from three to ten years . Computer software developed or obtained for internal use is amortized using the straight-line method over the estimated useful life of the software, generally three to seven years. Leasehold improvements are amortized over the shorter of their estimated useful lives or the term of the lease, and buildings are amortized over their expected useful lives. The costs of improvements that extend the life of a fixed asset are capitalized, while the cost of repairs and maintenance are expensed as incurred. Land is not depreciated.
Leases	Leases The Company and its Affiliates currently lease office space and equipment under various leasing arrangements. As these leases expire, it can be expected that in the normal course of business they will be renewed or replaced. Leases are classified as either capital leases or operating leases, as appropriate. Most lease agreements for office space that are classified as operating leases contain renewal options, rent escalation clauses or other inducements provided by the landlord. Rent expense is accrued to recognize lease escalation provisions and inducements provided by the landlord, if any, on a straight-line basis over the lease term.
Equity Investments in Affiliates	Equity Investments in Affiliates For equity method investments, the Company’s share of the Affiliate’s revenue without regard to expenses or the Company’s share of the Affiliate’s revenue less certain agreed-upon expenses, net of any amortization of intangible assets related to the Company’s investment, is included in Income from equity method investments. The Company’s share of income taxes incurred directly by Affiliates accounted for under the equity method is recorded within income taxes because these taxes generally represent the Company’s share of the taxes incurred by the Affiliate. The Company periodically evaluates its equity method investments for impairment. In such impairment evaluations, the Company assesses if the fair value of the investment has declined below its carrying value for a period considered to be other than temporary. If the Company determines that a decline in fair value below the carrying value of the investment is other than temporary, then the reduction in carrying value would be recognized in Income from equity method investments in the Consolidated Statements of Income.
Acquired Client Relationships and Goodwill	Acquired Client Relationships and Goodwill Each Affiliate in which the Company makes an investment has identifiable assets arising from contractual or other legal rights with their clients (“acquired client relationships”). In determining the value of acquired client relationships, the Company analyzes the net present value of these Affiliates’ existing client relationships based on a number of factors, including: the Affiliate’s historical and potential future operating performance; the Affiliate’s historical and potential future rates of attrition among existing clients; the stability and longevity of existing client relationships; the Affiliate’s recent, as well as long-term, investment performance; the characteristics of the firm’s products and investment styles; the stability and depth of the Affiliate’s management team; and the Affiliate’s history and perceived franchise or brand value. The Company has determined that certain of its mutual fund acquired client relationships meet the criteria to be considered indefinite-lived assets because the Company expects both the renewal of these contracts and the cash flows generated by these assets to continue indefinitely. Accordingly, the Company does not amortize these intangible assets, but instead reviews these assets annually or more frequently whenever events or circumstances occur indicating that the recorded indefinite-lived assets may be impaired. Each reporting period, the Company assesses whether events or circumstances have occurred that indicate that the indefinite life criteria are no longer met. If the indefinite life criteria are no longer met, the Company would assess whether the carrying value of the assets exceeds its fair value, an impairment loss would be recorded in an amount equal to any such excess and these assets would be reclassified to definite-lived. The expected useful lives of definite-lived acquired client relationships are determined based on an analysis of the historical and projected attrition rates of each Affiliate’s existing clients, and other factors that may influence the expected future economic benefit the Company will derive from the relationships. The expected lives of definite-lived acquired client relationships are analyzed annually or more frequently whenever events or circumstances have occurred that indicate the expected useful lives may no longer be appropriate. The Company tests for the possible impairment of indefinite and definite-lived intangible assets annually or more frequently whenever events or changes in circumstances indicate that the carrying amount of the asset is not recoverable. If such indicators exist, the Company compares the fair value of the asset to the carrying value of the asset. If the carrying value is greater than the fair value, an impairment loss would be recorded in Intangible amortization and impairments. Goodwill represents the future economic benefits arising from assets acquired in a business combination that are not individually identified and separately recognized, and is reported within the segments in which the Affiliate operates. Goodwill is not amortized, but is instead reviewed for impairment. The Company assesses goodwill for impairment at least annually, or more frequently whenever events or circumstances occur indicating that the recorded goodwill may be impaired. If the carrying amount of goodwill exceeds the fair value, an impairment loss would be recorded in Intangible amortization and impairments.
Issuance Costs	Issuance Costs Issuance costs related to Company’s senior bank debt are amortized over the remaining term of the credit facility and term loan. Costs incurred to issue debt are amortized over the shorter of the period to the first investor put or the Company’s estimate of the expected term of the security. Costs associated with financial instruments that are not required to be accounted for separately as derivative instruments are charged directly to stockholders’ equity.
Derivative Financial Instruments	Derivative Financial Instruments The Company may utilize financial instruments, specifically interest rate derivative contracts to hedge certain interest rate exposures. In entering into these contracts, the Company intends to offset cash flow gains and losses that occur on its existing debt obligations with cash flow gains and losses on the contracts hedging these obligations. From time to time, the Company’s Affiliates use foreign currency forward contracts to hedge the risk of currency exchange rate movements. In entering into these contracts, the Affiliates intend to offset cash flow gains and losses on projected foreign currency-denominated revenues and expenses as a result of variability in foreign currency exchange rates. The Company records derivatives on the balance sheet at fair value. If the Company’s derivatives qualify as cash flow hedges, the effective portion of the unrealized gain or loss is recorded in Accumulated other comprehensive income as a separate component of stockholders’ equity and reclassified into earnings when the hedged cash flows are recorded in earnings. Hedge effectiveness is generally measured by comparing the present value of the cumulative change in the expected future variable cash flows of the hedged contract with the present value of the cumulative change in the expected future variable cash flows of the hedged item. To the extent that the critical terms of the hedged item and the derivative are not identical, hedge ineffectiveness would be reported in Investment and other (income) expense. If the Company’s derivatives do not qualify as cash flow or fair value hedges, changes in the fair value of the derivatives are recognized as a gain or loss in Investment and other (income) expense.
Contingent Payment Arrangements	Contingent Payment Arrangements The Company periodically enters into contingent payment arrangements in connection with its business combinations. In these arrangements, the Company agrees to pay additional consideration to the sellers to the extent that certain levels of revenue growth are achieved. For consolidated Affiliates, the Company estimates the fair value of these potential future obligations at the time a business combination is consummated and records a liability on its Consolidated Balance Sheet. The Company then accretes the obligation to its expected payment amount over the period until the arrangement is measured. If the Company’s expected payment amount subsequently changes, the obligation is reduced or increased in the current period resulting in a gain or loss, respectively. Both gains and losses resulting from changes to expected payments and the accretion of these obligations to their expected payment amounts are reflected within Imputed interest expense and contingent payment arrangements in the Company’s Consolidated Statements of Income. For Affiliates accounted for under the equity method, the Company records a liability when a payment becomes probable with a corresponding increase to the carrying value of the Affiliate.
Income Taxes	Income Taxes The Company accounts for income taxes using the liability method. Under this method, deferred taxes are recognized for the expected future tax consequences of temporary differences between the book carrying amounts and tax bases of the Company’s assets and liabilities. Deferred tax liabilities are generally attributable to intangible assets, convertible securities and deferred income. Deferred tax assets are generally attributable to deferred compensation, state and foreign loss carryforwards, and the benefit of uncertain tax positions. Intangible-related deferred tax liabilities are not recorded on U.S. basis differences related to the Company’s foreign investments in corporate stock because of the permanent nature of the Company’s investments. In measuring the amount of deferred taxes each period, the Company must project the impact on its future tax payments of any reversal of deferred tax liabilities (which would increase the Company’s tax payments), and any use of its state and foreign loss carryforwards (which would decrease its tax payments). In forming these estimates, the Company uses enacted federal, state and foreign income tax rates and makes assumptions about the apportionment of future taxable income to jurisdictions in which the Company has operations. An increase or decrease in foreign, federal or state income tax rates could have a material impact on the Company’s deferred income tax liabilities and assets and would result in a current income tax charge or benefit. The Company recognizes the financial statement benefit of an uncertain tax position only after considering the probability that a tax authority would sustain the position in an examination. For tax positions meeting a “more-likely-than-not” threshold, the amount recognized in the financial statements is the benefit expected to be realized upon settlement with the tax authority. For tax positions not meeting the threshold, no financial statement benefit is recognized. The Company recognizes interest and other charges relating to unrecognized tax benefits as additional tax expense. The Company regularly assesses the need for valuation allowances on its deferred tax assets, which would reduce these assets to their recoverable amounts. In forming these estimates, the Company makes assumptions of future taxable income that may be generated to utilize these assets, which have limited lives. If the Company determines that these assets will be realized, the Company records an adjustment to the valuation allowance, which would decrease tax expense in the period such determination was made. Likewise, should the Company determine that it would be unable to realize additional amounts of deferred tax assets, an adjustment to the valuation allowance would be charged to tax expense in the period such determination was made. The Company operates in various locations outside the U.S. and generates earnings from its foreign subsidiaries. The Company does not recognize a provision for U.S. income taxes or a deferred income tax liability on undistributed foreign earnings that are indefinitely reinvested.
Foreign Currency Translation	Foreign Currency Translation The assets and liabilities of Affiliates whose functional currency is not the U.S. dollar are translated into U.S. dollars using exchange rates in effect as of the balance sheet date. The revenue and expenses of these Affiliates are translated into U.S. dollars using average exchange rates for the relevant period. Because of the permanent nature of the Company’s investments, net translation exchange gains and losses are excluded from Net income and recorded in Other comprehensive income. Foreign currency transaction gains and losses are reflected in Investment and other (income) expense.
Concentration of Credit Risk	Concentration of Credit Risk Financial instruments that potentially subject the Company to significant concentrations of credit risk consist principally of cash investments. The Company maintains cash and cash equivalents, investments and, at times, certain financial instruments with various high credit-quality financial institutions. These financial institutions are typically located in countries in which AMG and its Affiliates operate. For AMG and certain Affiliates, cash deposits at a financial institution may exceed Federal Deposit Insurance Corporation insurance limits.
Revenue Recognition	Revenue Recognition The Company’s consolidated revenue primarily represents advisory fees billed by Affiliates for managing the assets of clients. Asset-based advisory fees are recognized as services are rendered and are based upon a percentage of the value of client assets managed. Any fees collected in advance are deferred and recognized as income over the period earned. Performance-based advisory fees are generally assessed as a percentage of the investment performance realized on a client’s account, generally over an annual period. Performance-based advisory fees are recognized when they are earned (i.e., when they become billable to customers and are not subject to claw-back) based on the contractual terms of agreements and when collection is reasonably assured. Carried interest is recognized upon the earlier of the termination of the investment product or when the likelihood of claw-back is improbable. Also included in revenue are commissions earned by broker-dealers, recorded on a trade date basis, and other service fees recorded as earned. The Company’s Affiliates have contractual arrangements with third parties to provide certain distribution-related services. These third parties are primarily compensated based on the value of client assets over time. Distribution-related revenues are presented gross of any related expenses when the Affiliate is the principal in its role as primary obligor under its sales and distribution arrangements. Distribution-related expenses are presented within Selling, general and administrative expenses.
Earnings Per Share	Earnings Per Share The calculation of basic earnings per share is based on the weighted average number of shares of the Company’s common stock outstanding during the period. Diluted earnings per share is similar to basic earnings per share, but adjusts for the dilutive effect of the potential issuance of incremental shares of the Company’s common stock. The Company had convertible securities outstanding during the periods presented and is required to apply the if-converted method to these securities in its calculation of diluted earnings per share. Under the if-converted method, shares that are issuable upon conversion are deemed outstanding, regardless of whether the securities are contractually convertible into the Company’s common stock at that time. For this calculation, the interest expense (net of tax) attributable to these dilutive securities is added back to Net income (controlling interest), reflecting the assumption that the securities have been converted. Issuable shares for these securities and related interest expense are excluded from the calculation if an assumed conversion would be anti-dilutive to diluted earnings per share.
Share-Based Compensation Plans	Share-Based Compensation Plans The Company recognizes expenses for all share-based payments based on their grant date fair values over the requisite service period. The Company reports any tax benefits realized upon the exercise of stock options that are in excess of the expense recognized for reporting purposes as a financing activity in the Company’s Consolidated Statements of Cash Flows. If the tax benefit realized is less than the expense, the tax shortfall is recognized in stockholders’ equity. To the extent the expense exceeds available windfall tax benefits, it is recognized in the Consolidated Statements of Income. The Company was permitted to calculate its cumulative windfall tax benefits for the purposes of accounting for future tax shortfalls. The Company elected to apply the long-form method for determining the pool of windfall tax benefits.
Segment Information	Segment Information Management has assessed and determined that the Company operates in three business segments representing the Company’s three principal distribution channels: Institutional, Mutual Fund and High Net Worth, each of which has different client relationships. Revenue and income from equity method investments in the Institutional distribution channel is earned from relationships with public and private client entities, including foundations, endowments, sovereign wealth funds and retirement plans for corporations and municipalities. Revenue and income from equity method investments in the Mutual Fund distribution channel is earned from advisory or sub-advisory relationships with active return oriented mutual funds, UCITS and other retail products. Revenue and income from equity method investments in the High Net Worth distribution channel is earned from relationships with high net worth and ultra-high net worth individuals, families, trusts, foundations, endowments and retirement plans. In measuring Net income (controlling interest) by segment, the Company’s share of expenses incurred directly at Affiliates and AMG Funds is allocated to a particular segment pro rata to the revenue generated by the Affiliate and AMG Funds in such segment. All other operating and non-operating expenses not incurred directly by an Affiliate or AMG Funds are generally allocated to segments based on the relative contribution to earnings of the applicable Affiliate or AMG Funds in each segment.
Recent Accounting Developments	Recent Accounting Developments In May 2014, the Financial Accounting Standards Board (the “FASB”) issued a final standard on revenue from contracts with customers. The new standard provides a comprehensive model for revenue recognition. The new standard is effective for interim and fiscal periods beginning after December 15, 2017. The Company is evaluating the impact of this standard on its Consolidated Financial Statements. In February 2015, the FASB issued a new standard that amended the current consolidation guidance. The new standard changes the analysis required to determine whether an entity is a variable interest entity and should be consolidated. The new standard is effective for interim and fiscal periods beginning after December 15, 2015. The Company is evaluating the impact of this new standard on its Consolidated Financial Statements. In April 2015, the FASB issued a new standard to reduce diversity in the presentation of debt issuance costs. The new standard requires debt issuance costs to be presented on the balance sheet as a deduction from the related debt. The new standard is effective for interim and fiscal periods beginning after December 15, 2015. The Company does not anticipate that this new standard will have a material impact on its Consolidated Financial Statements. In April 2015, the FASB issued a new standard amending the disclosure requirements for investments in certain entities that calculate net asset value per share. The new standard removes, from the fair value hierarchy, investments for which the net asset value is used as a practical measure of fair value. The new standard is effective for interim and fiscal periods beginning after December 15, 2015. The Company does not anticipate that this new standard will have a material impact on its Consolidated Financial Statements. In September 2015, the FASB issued a new standard requiring an acquirer to recognize and disclose adjustments to provisional purchase price allocations, performed in connection with business combinations, in the reporting period in which the adjustments are determined. The new standard is effective for interim and fiscal periods beginning after December 15, 2015. The Company is evaluating the impact of this new standard on its Consolidated Financial Statements. In January 2016, the FASB issued a new standard that changes the accounting for equity investments, financial liabilities under the fair value option and the presentation and disclosure requirements for financial instruments. Under the new guidance, all equity investments in unconsolidated entities (other than those accounted for using the equity method of accounting) will generally be measured at fair value through earnings. The new standard is effective for interim and fiscal periods beginning after December 15, 2017. The Company is evaluating the impact of this new standard on its Consolidated Financial Statements.
Fair value of financial instruments	The following are descriptions of the significant financial assets and liabilities measured at fair value and the fair value methodologies used. Cash equivalents consist primarily of highly liquid investments in daily redeeming money market funds that are classified as Level 1. Investments in marketable securities consist primarily of investments in publicly traded securities and in funds advised by Affiliates that are valued using net asset value (“NAV”). Publicly traded securities and investments in daily redeeming funds that calculate NAVs are classified as Level 1. Other investments consist primarily of funds advised by Affiliates and are valued using NAV. Investments in daily redeeming funds that calculate NAVs are classified as Level 1. Investments in funds that permit redemptions monthly or quarterly are classified as Level 2. Investments in funds that are subject to longer redemption restrictions are classified as Level 3. The fair value of Level 3 assets is primarily determined using NAV one quarter in arrears (adjusted for current period calls and distributions). Contingent payment arrangements represent the present value of the expected future settlement of contingent payment arrangements related to the Company’s investments in consolidated Affiliates. The significant unobservable inputs that are used in the fair value measurement of these obligations are growth and discount rates. Increases in the growth rate result in a higher obligation while an increase in the discount rate results in a lower obligation. Obligations to related parties include agreements to repurchase Affiliate equity and liabilities, offsetting certain investments that are held by the Company but economically attributable to a related party. The significant unobservable inputs that are used in the fair value measurement of the agreements to repurchase Affiliate equity are growth and discount rates. Increases in the growth rate result in a higher obligation while an increase in the discount rate results in a lower obligation. The liability to a related party is measured based upon certain investments held by the Company, the fair value of which is determined using NAV one quarter in arrears adjusted for current period calls and distributions. Interest rate swaps and foreign currency forward contracts use model-derived valuations in which all significant inputs are observable in active markets to determine the fair value of these derivatives. It is the Company’s policy to value financial assets or liabilities transferred as of the beginning of the period in which the transfer occurs.

Investments in Marketable Sec36

Investments in Marketable Securities (Tables)	12 Months Ended
	Dec. 31, 2015
Marketable Securities [Abstract]
Summary of the Cost, Gross Unrealized Gains and Losses, and Fair Value of Investments	The following is a summary of the cost, gross unrealized gains and losses and fair value of investments classified as available-for-sale and trading: Available-for-Sale Trading December 31, 2014 December 31, 2015 December 31, 2014 December 31, 2015 Cost $ 125.6 $ 104.7 $ 19.5 $ 19.8 Unrealized Gains 42.8 77.6 2.9 1.9 Unrealized Losses (18.1 ) (1.8 ) (0.1 ) (2.3 ) Fair Value $ 150.3 $ 180.5 $ 22.3 $ 19.4

Variable Interest Entities (Tab

Variable Interest Entities (Tables)	12 Months Ended
	Dec. 31, 2015
Variable Interest Entities
Schedule of Net Assets and Liabilities and Maximum Risk of Losses Related to Unconsolidated VIEs	The net assets and liabilities of these unconsolidated VIEs and the Company’s maximum risk of loss were as follows: December 31, 2014 December 31, 2015 Category of Investment Unconsolidated VIE Net Assets Carrying Value and Maximum Risk of Loss Unconsolidated VIE Net Assets Carrying Value and Maximum Risk of Loss Sponsored investment funds $ 8,550.4 $ 1.2 $ 6,688.9 $ 1.4

Senior Notes (Tables)

Senior Notes (Tables)	12 Months Ended
	Dec. 31, 2015
Debt Disclosure [Abstract]
Summary of Principal Terms of Senior Notes	at December 31, 2015 had three senior notes outstanding, the principal terms of which are summarized below. 2024 Senior Notes 2025 Senior Notes 2042 Senior Notes Issue date February 2014 February 2015 August 2012 Maturity date February 2024 August 2025 August 2042 Potential Call Date Any Time (1) Any Time (1) August 2017 Par value (in millions) $ 400.0 $ 350.0 $ 200.0 Call Price As Defined (1) As Defined (1) At Par Stated coupon 4.25 % 3.50 % 6.375 % Coupon frequency Semi-annually Semi-annually Quarterly __________________________ (1) The 2024 and 2025 senior notes may be redeemed at any time, in whole or in part, at a make-whole redemption price plus accrued and unpaid interest.

Convertible Securities (Tables)

Convertible Securities (Tables)	12 Months Ended
	Dec. 31, 2015
Debt Disclosure [Abstract]
Schedule of Carrying Value of Convertible Securities	The carrying values of the Company’s convertible securities were as follows: December 31, 2014 December 31, 2015 Carrying Value Principal Amount at Maturity Carrying Value Principal Amount at Maturity 2007 junior convertible securities (1) $ 303.1 $ 430.8 $ 305.2 $ 430.8 __________________________ (1) The carrying value is accreted to the principal amount at maturity over a remaining life of 22 years.

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2015
Fair Value Disclosures [Abstract]
Schedule of Fair Value of Financial Assets and Liabilities Measured on a Recurring Basis	The following tables summarize the Company’s financial assets and liabilities that are measured at fair value on a recurring basis: Fair Value Measurements December 31, 2014 Level 1 Level 2 Level 3 Financial Assets Cash equivalents $ 59.1 $ 59.1 $ — $ — Investments in marketable securities (1) Trading securities 22.3 22.3 — — Available-for-sale securities 150.3 150.3 — — Other investments 167.2 13.6 19.4 134.2 Financial Liabilities Contingent payment arrangements (2) $ 59.3 $ — $ — $ 59.3 Obligations to related parties (2) 93.1 — — 93.1 Interest rate swaps 1.4 — 1.4 — Foreign currency forward contracts (3) 0.5 — 0.5 — Fair Value Measurements December 31, 2015 Level 1 Level 2 Level 3 Financial Assets Cash equivalents $ 65.9 $ 65.9 $ — $ — Investments in marketable securities (1) Trading securities 19.4 19.4 — — Available for sale securities 180.5 180.5 — — Other investments 149.3 20.7 2.6 126.0 Financial Liabilities Contingent payment arrangements (2) $ 10.2 $ — $ — $ 10.2 Obligations to related parties (2) 137.3 — — 137.3 __________________________ (1) Principally investments in equity securities. (2) Amounts are presented within Other liabilities. (3) Amounts are presented within Other assets or Other liabilities.
Schedule of Changes in Level 3 Financial Assets and Liabilities	The following table presents the changes in Level 3 assets and liabilities: For the Years Ended December 31, 2014 2015 Other Investments Contingent Payment Arrangements Obligations to Related Parties Other Investments Contingent Payment Arrangements Obligations to Related Parties Balance, beginning of period $ 131.8 $ 50.2 $ 76.9 $ 134.2 $ 59.3 $ 93.1 Net gains/losses 11.4 (1) 9.1 (2) 5.5 (3) (5.5 ) (1) (40.9 ) (2) 4.6 (3) Purchases and issuances 17.4 — 96.7 16.3 9.3 164.1 Settlements and reductions (26.4 ) — (86.0 ) (25.5 ) (17.5 ) (124.5 ) Net transfers in and/or out of Level 3 — — — 6.5 — — Balance, end of period $ 134.2 $ 59.3 $ 93.1 $ 126.0 $ 10.2 $ 137.3 Net change in unrealized gains/losses relating to instruments still held at the reporting date $ 17.1 $ 9.1 $ (0.1 ) $ 6.1 $ (40.9 ) $ (7.3 ) __________________________ (1) Gains and losses on Other investments are recorded in Investment and other (income) expense. (2) Accretion and changes to the Company’s contingent payment arrangements are recorded in Imputed interest expense and contingent payment arrangements. (3) Gains and losses associated with agreements to repurchase Affiliate equity are recorded in Imputed interest expense and contingent payment arrangements. Gains and losses related to liabilities offsetting certain investments are recorded in Investment and other (income) expense.
Schedule of Quantitative Information	The following table presents certain quantitative information about the significant unobservable inputs used in valuing the Company’s Level 3 financial liabilities: Quantitative Information about Level 3 Fair Value Measurements Valuation Techniques Unobservable Input Fair Value at Range at December 31, 2014 Fair Value at Range at December 31, 2015 Contingent payment arrangements Discounted cash flow Growth rates $ 59.3 6% $ 10.2 3% - 8% Discount rates 15% 15% Affiliate equity repurchase obligations Discounted cash flow Growth rates 21.5 5% - 9% 62.3 1% - 9% Discount rates 15% - 16% 14% - 15%
Schedule of Investments	The following table summarizes the nature of these investments and any related liquidity restrictions or other factors that may impact the ultimate value realized: December 31, 2014 December 31, 2015 Category of Investment Fair Value Unfunded Commitments Fair Value Unfunded Commitments Private equity (1) $ 134.2 $ 67.8 $ 126.0 $ 76.8 Other funds (2) 75.8 — 72.3 — $ 210.0 $ 67.8 $ 198.3 $ 76.8 __________________________ (1) These funds primarily invest in a broad range of private equity funds and make direct investments. Distributions will be received as the underlying assets are liquidated over the life of the funds, which is generally 15 years . (2) These are multi-disciplinary funds that invest across various asset classes and strategies, including long/short equity, credit and real estate. Investments are generally redeemable on a daily or quarterly basis.
Summary of Financial Liabilities not Carried at Fair Value	The following table summarizes the Company’s other financial liabilities not carried at fair value: December 31, 2014 December 31, 2015 Carrying Amount Fair Value Carrying Amount Fair Value Fair Value Hierarchy Senior notes $ 736.8 $ 786.2 $ 944.6 $ 966.3 Level 2 Convertible securities 303.1 532.1 305.2 483.6 Level 2

Business Combinations (Tables)

Business Combinations (Tables)	12 Months Ended
	Dec. 31, 2015
Business Combinations [Abstract]
Schedule of Purchase Price Allocation for Investments	The purchase price allocation for these investments was as follows: Total Consideration paid $ 76.1 Contingent payment obligations 9.3 Non-controlling interests 33.8 Enterprise value $ 119.2 Acquired client relationships $ 52.5 Tangible assets, net 2.4 Goodwill 64.3 $ 119.2
Schedule of Goodwill Allocation by Segment	The excess of the enterprise value over the separately identifiable net assets acquired was recorded as goodwill and the segment allocation was as follows: Total Institutional 14.4 % Mutual Fund — % High Net Worth 85.6 %
Schedule of Unaudited Pro Forma Financial Results	Unaudited pro-forma financial results are set forth below, assuming these investments occurred on January 1, 2014 and the Company’s structured partnership interests had been in effect for the entire period. For the Years Ended December 31, 2014 (Unaudited) 2015 (Unaudited) Revenue $ 2,538.2 $ 2,499.4 Net income (controlling interest) 454.5 517.9 Earnings per share (basic) 8.26 9.53 Earnings per share (diluted) 8.05 9.31

Goodwill and Acquired Client 42

Goodwill and Acquired Client Relationships (Tables)	12 Months Ended
	Dec. 31, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Changes in Goodwill	The following tables present the change in Goodwill and components of Acquired client relationships, net of the Company’s consolidated Affiliates: Goodwill Institutional Mutual Fund High Net Worth Total Balance, as of December 31, 2013 $ 1,076.3 $ 928.1 $ 337.3 $ 2,341.7 Goodwill acquired 97.2 208.1 39.2 344.5 Foreign currency translation (14.4 ) (10.9 ) (8.1 ) (33.4 ) Balance, as of December 31, 2014 $ 1,159.1 $ 1,125.3 $ 368.4 $ 2,652.8 Goodwill acquired 9.2 — 55.1 64.3 Foreign currency translation (27.0 ) (5.8 ) (15.9 ) (48.7 ) Balance, as of December 31, 2015 $ 1,141.3 $ 1,119.5 $ 407.6 $ 2,668.4
Schedule of Changes in, and the Components of, Acquired Client Relationships	Acquired Client Relationships Definite-lived Indefinite-lived Total Gross Book Value Accumulated Amortization Net Book Value Net Book Value Net Book Value Balance, as of December 31, 2013 $ 1,039.5 $ (442.8 ) $ 596.7 $ 864.0 $ 1,460.7 New Investments 220.3 — 220.3 244.7 465.0 Amortization and impairments — (122.2 ) (122.2 ) — (122.2 ) Foreign currency translation (4.7 ) — (4.7 ) (20.4 ) (25.1 ) Balance, as of December 31, 2014 $ 1,255.1 $ (565.0 ) $ 690.1 $ 1,088.3 $ 1,778.4 New Investments 52.5 — 52.5 — 52.5 Amortization and impairments — (115.4 ) (115.4 ) — (115.4 ) Foreign currency translation (5.8 ) — (5.8 ) (23.3 ) (29.1 ) Balance, as of December 31, 2015 $ 1,301.8 $ (680.4 ) $ 621.4 $ 1,065.0 $ 1,686.4

Equity Method Investments in 43

Equity Method Investments in Affiliates (Tables)	12 Months Ended
	Dec. 31, 2015
Equity Method Investments and Joint Ventures [Abstract]
Schedule of Financial Information for Affiliates Accounted for Under the Equity Method	The following table presents summarized financial information for Affiliates accounted for under the equity method. For the Years Ended December 31, 2013 2014 2015 Revenue (1) $ 1,589.6 $ 1,869.3 $ 2,217.1 Net income 1,321.9 253.8 431.5 December 31, 2014 2015 Assets (2) $ 34,729.2 $ 30,663.4 Liabilities and Non-controlling interest (2) 33,048.6 29,434.7 __________________________ (1) Revenue includes advisory fees for asset management services and net investment income from consolidated investment partnerships. (2) Assets consist primarily of investment securities in consolidated investment partnerships, which are generally held by non-controlling interests.

Fixed Assets and Lease Commit44

Fixed Assets and Lease Commitments (Tables)	12 Months Ended
	Dec. 31, 2015
Fixed Assets and Lease Commitments [Abstract]
Schedule of Fixed Assets	Fixed assets consisted of the following: December 31, 2014 2015 Building and leasehold improvements $ 84.1 $ 104.7 Software 40.8 45.4 Equipment 38.3 39.9 Furniture and fixtures 17.5 22.4 Land, improvements and other 18.7 18.6 Fixed assets, at cost 199.4 231.0 Accumulated depreciation and amortization (104.0 ) (116.9 ) Fixed assets, net $ 95.4 $ 114.1
Schedule of Aggregate Future Minimum Payments for Operating Leases	At December 31, 2015 , the Company’s aggregate future minimum payments for operating leases having initial or non-cancelable lease terms greater than one year were payable as follows: Required Minimum Payments (1) 2016 $ 36.0 2017 33.7 2018 31.0 2019 29.5 2020 28.4 Thereafter 82.1 __________________________ (1) The controlling interest portion is $10.7 million through 2016, $11.0 million each in 2017 and in 2018, $10.6 million in 2019, $10.1 million in 2020 and $38.7 million thereafter.

Payables and Accrued Liabilit45

Payables and Accrued Liabilities (Tables)	12 Months Ended
	Dec. 31, 2015
Payables and Accruals [Abstract]
Schedule of Accounts Payable and Accrued Liabilities	Payables and accrued liabilities consisted of the following: December 31, 2014 2015 Accrued compensation and distributions $ 491.3 $ 455.0 Unsettled fund share payables 78.3 76.6 Accrued income taxes 59.8 67.9 Accrued share repurchases 47.8 — Accrued professional fees 26.9 31.4 Other 104.2 98.5 $ 808.3 $ 729.4

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	12 Months Ended
	Dec. 31, 2015
Stockholders' Equity Note [Abstract]
Schedule of Recent Share Repurchase Activity	The following is a summary of the Company’s recent share repurchase activity: Period Shares Repurchased Average Price 2013 0.1 $ 184.89 2014 1.2 204.72 2015 1.7 209.39

Share-Based Compensation (Table

Share-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Summary of Recent Share-Based Compensation Expense	The following is a summary of share-based compensation expense: Period Share-Based Compensation Expense Tax Benefit 2013 $ 27.5 $ 10.6 2014 29.3 11.3 2015 34.2 13.2
Schedule of Transactions of the Company's Stock Options	The following table summarizes the transactions of the Company’s stock options: Stock Options Weighted Average Exercise Price Weighted Average Remaining Contractual Life (years) Unexercised options outstanding—January 1, 2015 2.3 $ 83.42 Options granted 0.0 207.61 Options exercised (0.9 ) 65.95 Options forfeited (0.0 ) 101.29 Unexercised options outstanding—December 31, 2015 1.4 96.18 2.2 Exercisable at December 31, 2015 1.3 94.43 2.1
Schedule of Assumptions Used to Determine Fair Value of Options Granted	The fair value of options granted was estimated using the Black-Scholes option pricing model. The weighted average fair value of options granted during the years ended December 31, 2013 , 2014 and 2015 was $61.82 , $60.20 , and $54.92 per option, respectively, based on the weighted-average grant date assumptions stated below. For the Years Ended December 31, 2013 2014 2015 Dividend yield 0.0 % 0.0 % 0.0 % Expected volatility (1) 34.4 % 29.7 % 26.7 % Risk-free interest rate (2) 1.5 % 1.8 % 1.5 % Expected life of options (in years) (3) 5.0 5.0 5.0 Forfeiture rate (3) 0.0 % 0.0 % 0.0 % __________________________ (1) Expected volatility is based on historical and implied volatility. (2) Risk-free interest rate is based on the U.S. Treasury yield curve in effect at the date of grant. (3) Expected life of options (in years) is based on the Company’s historical data and expected exercise behavior.
Summary of Transactions of the Company's Restricted Stock	The following table summarizes the transactions of the Company’s restricted stock: Restricted Stock Weighted Average Grant Date Value Unvested units—January 1, 2015 0.4 $ 182.83 Units granted 0.3 197.59 Units vested (0.1 ) 174.19 Units forfeited (0.0 ) 190.23 Unvested units—December 31, 2015 0.6 192.04

Affiliate Equity (Tables)

Affiliate Equity (Tables)	12 Months Ended
	Dec. 31, 2015
Affiliate Equity
Summary of Affiliate Equity Expense	The following is a summary of Affiliate equity expense: 2013 2014 2015 Controlling interest $ 56.4 $ 47.4 $ 16.9 Tax benefit (21.7 ) (18.2 ) (6.5 ) Controlling interest, net $ 34.7 $ 29.2 $ 10.4 Non-controlling interest 15.9 37.0 51.6 Total $ 50.6 $ 66.2 $ 62.0
Summary of Affiliate Equity Unrecognized Expense	The following is a summary of unrecognized Affiliate equity expense: Unrecognized Affiliate Equity Expense Period Controlling Interest Remaining Life Non-Controlling Interest Remaining Life 2013 $ 36.1 3 years $ 32.1 7 years 2014 29.5 3 years 41.6 6 years 2015 22.4 3 years 51.9 5 years
Schedule of the Changes in Redeemable Non-controlling Interests	The following table presents the changes in Redeemable non-controlling interests: 2014 2015 Balance, as of January 1 $ 641.9 $ 645.5 Repurchases of redeemable Affiliate equity (61.7 ) (161.3 ) Transfers from Non-controlling interests 22.7 49.5 Changes in redemption value 43.0 81.6 Decrease attributable to consolidated products (0.4 ) (2.8 ) Balance, as of December 31 $ 645.5 $ 612.5
Schedule of the Effect of Changes in the Company's Ownership Interest in its Affiliates on the Controlling Interest's Equity	The following schedule discloses the effect of changes in the Company’s ownership interests in its Affiliates on the controlling interest’s equity: For the Years Ended December 31, 2013 2014 2015 Net income (controlling interest) $ 360.5 $ 452.1 $ 516.0 Increase in controlling interest paid-in capital related to Affiliate equity issuances 13.1 2.5 0.7 Decrease in controlling interest paid-in capital related to Affiliate equity repurchases (87.1 ) (35.8 ) (89.8 ) Net income attributable to controlling interest and transfers (to) or from Non-controlling interests $ 286.5 $ 418.8 $ 426.9

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Schedule of Income Tax Provision Attributable to Controlling and Non-Controlling Interests	The consolidated income tax provision included taxes attributable to the controlling interest and, to a lesser extent, taxes attributable to non-controlling interests follows: For the Years Ended December 31, 2013 2014 2015 Controlling Interests: Current tax $ 153.1 $ 149.8 $ 152.4 Intangible-related deferred taxes 38.1 47.8 77.7 Other deferred taxes (6.2 ) 15.8 21.2 Total controlling interests 185.0 213.4 251.3 Non-controlling Interests: Current tax $ 13.3 $ 15.3 $ 9.8 Deferred taxes (4.2 ) (0.8 ) (4.2 ) Total non-controlling interests 9.1 14.5 5.6 Provision for income taxes $ 194.1 $ 227.9 $ 256.9 Income before income taxes (controlling interest) $ 545.5 $ 665.5 $ 767.3 Effective tax rate attributable to controlling interests (1) 33.9 % 32.1 % 32.8 % __________________________ (1) Taxes attributable to the controlling interest divided by Income before income taxes (controlling interest).
Schedule of Consolidated Provision for Income Taxes	A summary of the consolidated provision for income taxes follows: For the Years Ended December 31, 2013 2014 2015 Current: Federal $ 104.1 $ 93.8 $ 106.3 State 21.1 27.1 18.3 Foreign 41.2 44.2 37.6 Total current 166.4 165.1 162.2 Deferred: Federal 38.1 72.5 97.9 State 8.9 1.1 14.2 Foreign (19.3 ) (10.8 ) (17.4 ) Total deferred 27.7 62.8 94.7 Provision for income taxes $ 194.1 $ 227.9 $ 256.9
Schedule of Components of Income before Income Taxes	The components of income before income taxes consisted of the following: For the Years Ended December 31, 2013 2014 2015 Domestic $ 604.0 $ 784.1 $ 827.6 International 259.7 229.5 263.0 $ 863.7 $ 1,013.6 $ 1,090.6
Schedule of Effective Income Tax Rate Computed Using Income before Income Taxes and Applying U.S. Federal Income Tax Rate	The Company’s effective income tax rate differed from the amount computed by using income before income taxes and applying the U.S. federal income tax rate because of the effect of the following items: For the Years Ended December 31, 2013 2014 2015 Tax at U.S. federal income tax rate 35.0 % 35.0 % 35.0 % State income taxes, net of federal benefit (1) 2.8 2.1 2.6 Effect of foreign operations (2.5 ) (5.3 ) (3.5 ) Other (1.4 ) 0.3 (1.3 ) Effective tax rate (controlling interest) 33.9 32.1 32.8 Effect of income from non-controlling interests (11.4 ) (9.6 ) (9.2 ) Effect tax rate 22.5 % 22.5 % 23.6 % __________________________ (1) State income taxes included changes related to state valuation allowances.
Schedule of Components of Deferred Tax Assets and Liabilities	The components of deferred tax assets and liabilities were as follows: December 31, 2014 2015 Deferred Tax Assets Deferred compensation $ 26.8 $ 30.5 State net operating loss carryforwards 15.2 17.1 Tax benefit of uncertain tax positions 16.0 14.6 Accrued expenses 19.6 4.4 Foreign loss carryforwards 11.5 12.3 Other 1.4 — Total deferred tax assets 90.5 78.9 Valuation allowance (18.4 ) (20.5 ) Deferred tax assets, net of valuation allowance $ 72.1 $ 58.4 Deferred Tax Liabilities Intangible asset amortization $ (270.9 ) $ (320.2 ) Non-deductible intangible amortization (126.4 ) (109.8 ) Convertible securities interest (92.5 ) (99.8 ) Deferred income (74.0 ) (92.8 ) Other — (1.5 ) Total deferred tax liabilities (563.8 ) (624.1 ) Net deferred tax liability $ (491.7 ) $ (565.7 )
Schedule of Reconciliation of Beginning and Ending Amount of Unrecognized Tax Benefits	A reconciliation of the beginning and ending amount of unrecognized tax benefits follows: For the Years Ended December 31, 2013 2014 2015 Balance, as of January 1 $ 22.6 $ 20.4 $ 28.8 Additions based on current year tax positions 4.1 2.6 2.2 Additions based on prior years’ tax positions — 10.8 1.6 Reductions for prior years’ tax provisions (0.1 ) — — Reductions related to lapses of statutes of limitations (5.4 ) (4.1 ) (4.3 ) Additions (reductions) related to foreign exchange rates (0.8 ) (0.9 ) (1.4 ) Balance, as of December 31 $ 20.4 $ 28.8 $ 26.9

Earnings Per Share (Tables)

Earnings Per Share (Tables)	12 Months Ended
	Dec. 31, 2015
Earnings Per Share [Abstract]
Schedule of Reconciliation of the Numerator and Denominator used in the Calculation of Basic and Diluted Earnings per Share	The following is a reconciliation of the numerator and denominator used in the calculation of basic and diluted earnings per share available to common stockholders. For the Years Ended December 31, 2013 2014 2015 Numerator Net income (controlling interest) $ 360.5 $ 452.1 $ 516.0 Interest expense on convertible securities, net of taxes 10.5 15.2 15.3 Net income (controlling interest), as adjusted $ 371.0 $ 467.3 $ 531.3 Denominator Average shares outstanding (basic) 53.1 55.0 54.3 Effect of dilutive instruments: Stock options and other awards 1.3 1.2 0.7 Forward sale 0.3 0.0 — Junior convertible securities 2.0 2.2 2.2 Average shares outstanding (diluted) 56.7 58.4 57.2
Diluted Earnings per Share Calculations Excluding the Anti-dilutive Effect of Shares	The diluted earnings per share calculations in the table above excluded the anti-dilutive effect of the following shares: For the Years Ended December 31, 2013 2014 2015 Stock options and other awards 0.1 0.0 0.0 Senior convertible securities 2.1 — — Junior convertible securities 2.2 0.4 —

Comprehensive Income (Tables)

Comprehensive Income (Tables)	12 Months Ended
	Dec. 31, 2015
Stockholders' Equity Note [Abstract]
Summary of the Tax Effects Allocated to each Component of Other Comprehensive Income	The following tables show the tax effects allocated to each component of Other comprehensive income: For the Year Ended December 31, 2013 Pre-Tax Tax Benefit (Expense) Net of Tax Foreign currency translation gain (loss) $ (19.6 ) $ — $ (19.6 ) Change in net realized and unrealized gain (loss) on derivative securities 1.5 (0.5 ) 1.0 Change in net unrealized gain (loss) on investment securities 19.5 (8.0 ) 11.5 Other comprehensive income (loss) $ 1.4 $ (8.5 ) $ (7.1 ) For the Year Ended December 31, 2014 Pre-Tax Tax Benefit (Expense) Net of Tax Foreign currency translation gain (loss) $ (62.0 ) $ — $ (62.0 ) Change in net realized and unrealized gain (loss) on derivative securities 0.6 (0.3 ) 0.3 Change in net unrealized gain (loss) on investment securities 5.6 (2.2 ) 3.4 Other comprehensive income (loss) $ (55.8 ) $ (2.5 ) $ (58.3 ) For the Year Ended December 31, 2015 Pre-Tax Tax Benefit (Expense) Net of Tax Foreign currency translation gain (loss) $ (93.2 ) $ — $ (93.2 ) Change in net realized and unrealized gain (loss) on derivative securities 2.3 (0.4 ) 1.9 Change in net unrealized gain (loss) on investment securities 34.8 (12.7 ) 22.1 Other comprehensive income (loss) $ (56.1 ) $ (13.1 ) $ (69.2 )
Schedule of Components of Accumulated Other Comprehensive Income, Net of Taxes	The components of accumulated other comprehensive income (loss), net of taxes, were as follows: Foreign Currency Translation Adjustment Realized and Unrealized Losses on Derivative Securities Unrealized Gain (Loss) on Investment Securities (1) Total Balance, as of December 31, 2013 $ 56.6 $ (1.9 ) $ 19.5 $ 74.2 Other comprehensive income (loss) before reclassifications (62.0 ) 0.3 1.3 (60.4 ) Amounts reclassified from other comprehensive income — 0.0 2.1 2.1 Net other comprehensive income (loss) (62.0 ) 0.3 3.4 (58.3 ) Balance, as of December 31, 2014 $ (5.4 ) $ (1.6 ) $ 22.9 $ 15.9 Other comprehensive income (loss) before reclassifications (93.2 ) 0.8 13.5 (78.9 ) Amounts reclassified from other comprehensive income — 1.1 8.6 9.7 Net other comprehensive income (loss) (93.2 ) 1.9 22.1 (69.2 ) Balance, as of December 31, 2015 $ (98.6 ) $ 0.3 $ 45.0 $ (53.3 ) __________________________ (1) See Note 2 for amounts reclassified from Other comprehensive income.

Selected Quarterly Financial 52

Selected Quarterly Financial Data (Unaudited) (Tables)	12 Months Ended
	Dec. 31, 2015
Quarterly Financial Information Disclosure [Abstract]
Schedule of Quarterly Results of Operations	The following is a summary of the quarterly results of operations of the Company for the years ended December 31, 2014 and 2015 . 2014 First Quarter Second Quarter Third Quarter Fourth Quarter Revenue $ 593.1 $ 636.3 $ 640.3 $ 641.2 Operating income 193.9 198.4 224.2 198.7 Income before income taxes 208.2 239.1 253.4 312.8 Net income (controlling interest) 77.2 99.1 103.2 172.6 Earnings per share (diluted) 1.40 1.75 1.82 3.02 2015 First Quarter Second Quarter Third Quarter Fourth Quarter Revenue $ 635.0 $ 646.6 $ 613.1 $ 589.8 Operating income 231.4 195.2 215.2 193.2 Income before income taxes 290.3 262.0 249.1 289.2 Net income (controlling interest) 128.0 128.7 109.0 150.3 Earnings per share (diluted) 2.27 2.31 1.98 2.72

Segment Information (Tables)

Segment Information (Tables)	12 Months Ended
	Dec. 31, 2015
Segment Reporting [Abstract]
Schedule of Segment Information	As of and for the Year Ended December 31, 2013 Institutional Mutual Fund High Net Worth Total Revenue $ 948.7 $ 1,023.0 $ 217.1 $ 2,188.8 Net income (controlling interest) 219.9 103.4 37.2 360.5 Total assets 3,196.5 2,448.4 673.9 6,318.8 Goodwill 1,076.3 928.1 337.3 2,341.7 Equity method investments in Affiliates 942.6 77.7 103.0 1,123.3 As of and for the Year Ended December 31, 2014 Institutional Mutual Fund High Net Worth Total Revenue $ 1,022.8 $ 1,242.6 $ 245.5 $ 2,510.9 Net income (controlling interest) 227.0 180.1 45.0 452.1 Total assets 3,739.8 3,082.0 876.3 7,698.1 Goodwill 1,159.1 1,125.3 368.4 2,652.8 Equity method investments in Affiliates 1,533.8 150.3 99.4 1,783.5 As of and for the Year Ended December 31, 2015 Institutional Mutual Fund High Net Worth Total Revenue $ 979.4 $ 1,238.2 $ 266.9 $ 2,484.5 Net income (controlling interest) 229.3 229.7 57.0 516.0 Total assets 3,725.9 3,075.5 983.4 7,784.8 Goodwill 1,141.3 1,119.5 407.6 2,668.4 Equity method investments in Affiliates 1,609.3 185.7 142.1 1,937.1

Business and Summary of Signi54

Business and Summary of Significant Accounting Policies (Details)	12 Months Ended
	Dec. 31, 2015segmentchannel
Segment Information [Abstract]
Number of operating segments | segment	3
Number of principal distribution channels | channel	3
Office Equipment and Furniture and Fixtures | Minimum
Fixed Assets
Estimated useful life	3 years
Office Equipment and Furniture and Fixtures | Maximum
Fixed Assets
Estimated useful life	10 years
Computer software | Minimum
Fixed Assets
Estimated useful life	3 years
Computer software | Maximum
Fixed Assets
Estimated useful life	7 years

Investments in Marketable Sec55

Investments in Marketable Securities (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Cost of investments in marketable securities, gross unrealized gains and losses
Total investment	$ 199.9	$ 172.6
Realized gains (losses) on available-for-sale securities	$ 8.8	$ 3.4

Investments in Marketable Sec56

Investments in Marketable Securities - Summary of the Cost, Gross Unrealized Gains and Losses, and Fair Value of Investments (Details) - Equity Securities - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Available-for-Sale
Cost	$ 104.7	$ 125.6
Unrealized Gains	77.6	42.8
Unrealized Losses	(1.8)	(18.1)
Fair Value	180.5	150.3
Trading
Cost	19.8	19.5
Unrealized Gains	1.9	2.9
Unrealized Losses	(2.3)	(0.1)
Fair Value	$ 19.4	$ 22.3

Variable Interest Entities (Det

Variable Interest Entities (Details) - Sponsored Investment Funds - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Variable Interest Entities
Unconsolidated VIE net assets	$ 6,688.9	$ 8,550.4
Carrying value and maximum exposure to loss	$ 1.4	$ 1.2

Senior Bank Debt (Details)

Senior Bank Debt (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Debt Instrument
Term loan outstanding	$ 645	$ 855
Senior Unsecured Revolving Credit Facility
Debt Instrument
Maximum borrowing capacity	1,300
Maximum borrowing capacity, additional amount	500
Line of credit facility amount outstanding	$ 295	$ 605
Weighted average interest rate	2.52%	1.40%
Commitment fee amount	$ 1.9	$ 2.8
Senior Unsecured Term Loan
Debt Instrument
Principal Amount at Maturity	350
Maximum borrowing capacity, additional amount	100
Term loan outstanding	$ 350	$ 250
Weighted average interest rate on amount outstanding	1.45%	1.48%

Senior Notes (Details)

Senior Notes (Details)	12 Months Ended
	Dec. 31, 2015USD ($)senior_note
Debt Disclosure [Abstract]
Number of senior notes outstanding | senior_note	3
2022 Senior Notes
Debt Instrument
Senior Notes Redeemed, Canceled and Retired | $	$ 140,000,000
Stated interest rate	5.25%
Debt Instrument, Redemption Price, Percentage	100.00%

Senior Notes - Summary of Princ

Senior Notes - Summary of Principle Terms of Senior Notes (Details) - Senior Notes $ in Millions	Dec. 31, 2015USD ($)
2024 Senior Notes
Debt Instrument
Par value (in millions)	$ 400
Stated coupon	4.25%
2025 Senior Notes
Debt Instrument
Par value (in millions)	$ 350
Stated coupon	3.50%
2042 Senior Notes
Debt Instrument
Par value (in millions)	$ 200
Stated coupon	6.375%

Convertible Securities (Details

Convertible Securities (Details) $ / shares in Units, shares in Millions	12 Months Ended
	Dec. 31, 2015USD ($)trading_day$ / shares	Dec. 31, 2014USD ($)shares
Debt Instrument
Shares issued in conversion | shares		1.9
Loss recognized on conversion of debt securities		$ 18,800,000
2006 Junior Convertible Securities
Debt Instrument
Outstanding principal of junior convertible trust preferred securities		$ 300,000,000
2007 Junior Convertible Securities
Debt Instrument
Stated interest rate	5.15%
Principal amount at maturity	$ 50
Conversion ratio (in shares)	0.25
Conversion price (in usd per share) | $ / shares	$ 200
Redemption closing price trigger | $ / shares	$ 260
Number of trading days closing price has exceeded threshold | trading_day	20
Consecutive trading days	30 days
Deferred tax liability	$ 9,400,000
Common Stock
Debt Instrument
Shares issued in conversion | shares		1.9

Convertible Securities - Schedu

Convertible Securities - Schedule of Carrying Value of Convertible Securities (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2015	Dec. 31, 2014
Junior Convertible Trust Preferred Securities
Debt Instrument
Debt instrument term		22 years
2007 Junior Convertible Securities
Debt Instrument
Carrying value	[1]	$ 305.2	$ 303.1
Principal Amount at Maturity	[1]	$ 430.8	$ 430.8
[1]	The carrying value is accreted to the principal amount at maturity over a remaining life of 22 years

Forward Equity Sale Agreement (

Forward Equity Sale Agreement (Details)	Dec. 31, 2015USD ($)
Forward Equity Sale Agreements
Derivative remaining notional amount	$ 250,000,000

Derivative Financial Instrume64

Derivative Financial Instruments (Details) - Affiliate Partners - Foreign Exchange Forward $ in Millions	12 Months Ended
	Dec. 31, 2015USD ($)
Derivative Instruments, Gain (Loss) [Line Items]
Gain upon settlement of certain foreign currency forward contracts	$ 3.2
Loss upon settlement of certain foreign currency forward contracts	$ 1.7

Commitments and Contingencies (

Commitments and Contingencies (Details)	12 Months Ended
	Dec. 31, 2015USD ($)
Commitments and Contingencies
Co-investment commitments in partnership	$ 76,800,000
Prior Owner
Commitments and Contingencies
Reimbursable amount of investment commitments	15,200,000
Affiliate Partners
Commitments and Contingencies
Acquisition agreements contingency liability	85,600,000
Contingent payment obligations	14,000,000
Equity Method Investee
Commitments and Contingencies
Acquisition agreements contingency liability	166,500,000
Contingent payment obligations	$ 0

Fair Value Measurements - Sched

Fair Value Measurements - Schedule of Fair Value of Financial Assets and Liabilities Measured on a Recurring Basis (Details) - USD ($) $ in Millions		Dec. 31, 2015	Dec. 31, 2014
Investments in marketable securities
Other investments		$ 198.3	$ 210
Fair Value Measured on a Recurring Basis | Level 1
Financial Assets
Cash equivalents		65.9	59.1
Investments in marketable securities
Trading	[1]	19.4	22.3
Available-for-Sale	[1]	180.5	150.3
Other investments		20.7	13.6
Financial Liabilities
Contingent payment arrangements	[2]	0	0
Obligations to related parties	[2]	0	0
Interest rate swaps			0
Forward currency forward contracts	[3]		0
Fair Value Measured on a Recurring Basis | Level 2
Financial Assets
Cash equivalents		0	0
Investments in marketable securities
Trading	[1]	0	0
Available-for-Sale	[1]	0	0
Other investments		2.6	19.4
Financial Liabilities
Contingent payment arrangements	[2]	0	0
Obligations to related parties	[2]	0	0
Interest rate swaps			1.4
Forward currency forward contracts	[3]		0.5
Fair Value Measured on a Recurring Basis | Level 3
Financial Assets
Cash equivalents		0	0
Investments in marketable securities
Trading	[1]	0	0
Available-for-Sale	[1]	0	0
Other investments		126	134.2
Financial Liabilities
Contingent payment arrangements	[2]	10.2	59.3
Obligations to related parties	[2]	137.3	93.1
Interest rate swaps			0
Forward currency forward contracts	[3]		0
Fair Value Measured on a Recurring Basis | Fair Value
Financial Assets
Cash equivalents		65.9	59.1
Investments in marketable securities
Trading	[1]	19.4	22.3
Available-for-Sale	[1]	180.5	150.3
Other investments		149.3	167.2
Financial Liabilities
Contingent payment arrangements	[2]	10.2	59.3
Obligations to related parties	[2]	$ 137.3	93.1
Interest rate swaps			1.4
Forward currency forward contracts	[3]		$ 0.5
[1]	Principally investments in equity securities.
[2]	Amounts are presented within Other liabilities.
[3]	Amounts are presented within Other assets or Other liabilities.

Fair Value Measurements - Sch67

Fair Value Measurements - Schedule of Changes in Level 3 Financial Assets and Liabilities (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2015	Dec. 31, 2014
Other Investments
Changes in level 3 assets and liabilities
Balance, beginning of period		$ 134.2	$ 131.8
Net gains/losses	[1]	(5.5)	11.4
Purchases and issuances		16.3	17.4
Settlements and reductions		(25.5)	(26.4)
Net transfers in and/or out of Level 3		6.5	0
Balance, end of period		126	134.2
Net change in unrealized gains/losses relating to instruments still held at the reporting date		6.1	17.1
Contingent Payment Arrangements
Changes in level 3 assets and liabilities
Balance, beginning of period		59.3	50.2
Net gains/losses	[2]	(40.9)	9.1
Purchases and issuances		9.3	0
Settlements and reductions		(17.5)	0
Net transfers in and/or out of Level 3		0	0
Balance, end of period		10.2	59.3
Net change in unrealized gains/losses relating to instruments still held at the reporting date		(40.9)	9.1
Obligations to Related Parties
Changes in level 3 assets and liabilities
Balance, beginning of period		93.1	76.9
Net gains/losses	[3]	4.6	5.5
Purchases and issuances		164.1	96.7
Settlements and reductions		(124.5)	(86)
Net transfers in and/or out of Level 3		0	0
Balance, end of period		137.3	93.1
Net change in unrealized gains/losses relating to instruments still held at the reporting date		$ (7.3)	$ (0.1)
[1]	Gains and losses on Other investments are recorded in Investment and other (income) expense.
[2]	Accretion and changes to the Company’s contingent payment arrangements are recorded in Imputed interest expense and contingent payment arrangements.
[3]	Gains and losses associated with agreements to repurchase Affiliate equity are recorded in Imputed interest expense and contingent payment arrangements. Gains and losses related to liabilities offsetting certain investments are recorded in Investment and other (income) expense.

Fair Value Measurements - Sch68

Fair Value Measurements - Schedule of Quantitative Information (Details) - Discounted Cash Flow - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Contingent Payment Arrangements
Quantitative information for Level 3 Fair Value Measurements Liabilities
Fair value Liabilities	$ 10.2	$ 59.3
Growth rate (as a percent)		6.00%
Discount rate (as a percent)	15.00%	15.00%
Contingent Payment Arrangements | Minimum
Quantitative information for Level 3 Fair Value Measurements Liabilities
Growth rate (as a percent)	3.00%
Contingent Payment Arrangements | Maximum
Quantitative information for Level 3 Fair Value Measurements Liabilities
Growth rate (as a percent)	8.00%
Affiliate Equity Repurchase Obligations
Quantitative information for Level 3 Fair Value Measurements Liabilities
Fair value Liabilities	$ 62.3	$ 21.5
Affiliate Equity Repurchase Obligations | Minimum
Quantitative information for Level 3 Fair Value Measurements Liabilities
Growth rate (as a percent)	1.00%	5.00%
Discount rate (as a percent)	14.00%	15.00%
Affiliate Equity Repurchase Obligations | Maximum
Quantitative information for Level 3 Fair Value Measurements Liabilities
Growth rate (as a percent)	9.00%	9.00%
Discount rate (as a percent)	15.00%	16.00%

Fair Value Measurements - Sch69

Fair Value Measurements - Schedule of Investments (Details) - USD ($) $ in Millions		Dec. 31, 2015	Dec. 31, 2014
NAV of investments at fair value
Fair value		$ 198.3	$ 210
Unfunded commitments		76.8	67.8
Private Equity Fund-of-Funds
NAV of investments at fair value
Fair value	[1]	126	134.2
Unfunded commitments	[1]	76.8	67.8
Other Funds
NAV of investments at fair value
Fair value	[2]	72.3	75.8
Unfunded commitments	[2]	$ 0	$ 0
[1]	These funds primarily invest in a broad range of private equity funds and make direct investments. Distributions will be received as the underlying assets are liquidated over the life of the funds
[2]	These are multi-disciplinary funds that invest across various asset classes and strategies, including long/short equity, credit and real estate. Investments are generally redeemable on a daily or quarterly basis.

Fair Value Measurements - Summa

Fair Value Measurements - Summary of Financial Liabilities not Carried at Fair Value (Details) - Level 2 - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Senior notes	$ 944.6	$ 736.8
Convertible securities	305.2	303.1
Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Senior notes	966.3	786.2
Convertible securities	$ 483.6	$ 532.1

Business Combinations (Details)

Business Combinations (Details) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Business Acquisition
Amortization period for tax deductible goodwill	15 years
Payments to related party for contingent payment arrangements	$ 17,500,000	$ 0
Gain or loss recognized in changes of related party contingent liability	44,700,000	0	$ 10,300,000
New Affiliates
Business Acquisition
New affiliate investments contributed revenue	15,300,000
New affiliate investments contributed earnings	1,300,000
Other Liabilities
Business Acquisition
Liabilities to related party for contingent payments arrangements	$ 10,200,000	$ 59,300,000

Business Combinations - Schedul

Business Combinations - Schedule of Purchase Price Allocation for Investments (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Business Acquisition
Goodwill	$ 2,668.4	$ 2,652.8	$ 2,341.7
Baker Street Advisors, LLC and myCIO Wealth Partners, L.P.
Business Acquisition
Consideration paid	76.1
Contingent payment obligations	9.3
Non-controlling interests	33.8
Enterprise value	119.2
Acquired client relationships	52.5
Tangible assets, net	2.4
Goodwill	64.3
Total	$ 119.2

Business Combinations - Sched73

Business Combinations - Schedule of Goodwill Allocation by Segment (Details) - Baker Street Advisors, LLC and myCIO Wealth Partners, L.P.	Dec. 31, 2015
Institutional
Business Acquisition
Goodwill allocation to business segments (percent)	14.40%
Mutual Fund
Business Acquisition
Goodwill allocation to business segments (percent)	0.00%
High Net Worth
Business Acquisition
Goodwill allocation to business segments (percent)	85.60%

Business Combinations - Sched74

Business Combinations - Schedule of Unaudited Pro Forma Financial Results (Details) - Baker Street Advisors, LLC and myCIO Wealth Partners, L.P. - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Business Acquisition
Revenue	$ 2,499.4	$ 2,538.2
Net income (controlling interest)	$ 517.9	$ 454.5
Earnings per share—basic (in dollars per share)	$ 9.53	$ 8.26
Earnings per share—diluted (in dollars per share)	$ 9.31	$ 8.05

Goodwill and Acquired Client 75

Goodwill and Acquired Client Relationships (Details) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Goodwill
Intangible amortization and impairments	$ 115,400,000	$ 122,200,000	$ 128,200,000
Intangible Future Annual Amortization Expense, Year 1	37,100,000
Intangible Future Annual Amortization Expense, Year 2	37,100,000
Intangible Future Annual Amortization Expense, Year 3	37,100,000
Intangible Future Annual Amortization Expense, Year 4	37,100,000
Intangible Future Annual Amortization Expense, Year 5	37,100,000
Asset impairment charges	$ 0	0
Customer Relationships
Goodwill
Weighted average life	10 years
Intangible amortization and impairments	$ 115,400,000	$ 122,200,000
Intangible Future Annual Amortization Expense, Year 1	110,000,000
Intangible Future Annual Amortization Expense, Year 2	110,000,000
Intangible Future Annual Amortization Expense, Year 3	110,000,000
Intangible Future Annual Amortization Expense, Year 4	110,000,000
Intangible Future Annual Amortization Expense, Year 5	$ 110,000,000

Goodwill and Acquired Client 76

Goodwill and Acquired Client Relationships - Schedule of Changes in Goodwill (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Changes in goodwill
Balance at the beginning of the period	$ 2,652.8	$ 2,341.7
Goodwill acquired	64.3	344.5
Foreign currency translation	(48.7)	(33.4)
Balance at the end of the period	2,668.4	2,652.8
Institutional
Changes in goodwill
Balance at the beginning of the period	1,159.1	1,076.3
Goodwill acquired	9.2	97.2
Foreign currency translation	(27)	(14.4)
Balance at the end of the period	1,141.3	1,159.1
Mutual Fund
Changes in goodwill
Balance at the beginning of the period	1,125.3	928.1
Goodwill acquired	0	208.1
Foreign currency translation	(5.8)	(10.9)
Balance at the end of the period	1,119.5	1,125.3
High Net Worth
Changes in goodwill
Balance at the beginning of the period	368.4	337.3
Goodwill acquired	55.1	39.2
Foreign currency translation	(15.9)	(8.1)
Balance at the end of the period	$ 407.6	$ 368.4

Goodwill and Acquired Client 77

Goodwill and Acquired Client Relationships - Schedule of Changes in, and the Components of, Acquired Client Relationships (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Net Book Value
Net book value balance at the beginning of the period	$ 1,778.4
Net book value balance at the end of the period	1,686.4	$ 1,778.4
Customer Relationships
Definite-lived
Gross book value balance at the beginning of the period	1,255.1	1,039.5
Accumulated amortization balance at the beginning of the period	(565)	(442.8)
Net book value balance at the beginning of the period	690.1	596.7
New Investments	52.5	220.3
Amortization and impairments	(115.4)	(122.2)
Foreign currency translation	(5.8)	(4.7)
Gross book value balance at the end of the period	1,301.8	1,255.1
Accumulated amortization balance at the end of the period	(680.4)	(565)
Net book value balance at the end of the period	621.4	690.1
Indefinite-lived
Net book value balance at the beginning of the period	1,088.3	864
New investments	0	244.7
Amortization and Impairment	0	0
Foreign currency translation	(23.3)	(20.4)
Net book value balance at the end of the period	1,065	1,088.3
Net Book Value
Net book value balance at the beginning of the period	1,778.4	1,460.7
New investments	52.5	465
Amortization and Impairment	(115.4)	(122.2)
Foreign currency translation	(29.1)	(25.1)
Net book value balance at the end of the period	$ 1,686.4	$ 1,778.4

Equity Method Investments in 78

Equity Method Investments in Affiliates (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Jan. 04, 2016
Schedule of Equity Method Investments
Amortization period for tax deductible goodwill	15 years
Amortization expense during the period	$ 115.4	$ 122.2	$ 128.2
Annual amortization expense Year 1	37.1
Annual amortization expense Year 2	37.1
Annual amortization expense Year 3	37.1
Annual amortization expense Year 4	37.1
Annual amortization expense Year 5	37.1
Undistributed earnings from equity method investments	$ 101.5
Acquired Client Relationships Under Equity Method Investments
Schedule of Equity Method Investments
Weighted average life	14 years
Amortization expense during the period	$ 34.3	$ 32.3
Ivory Investment Management, L.P. | Acquired Client Relationships Under Equity Method Investments
Schedule of Equity Method Investments
Acquired client relationships	200
Payment of contingent payment liability	$ 23.3
Abax Investments (Pty) Ltd and Ivory Investment Management, L.P. [Member] | Acquired Client Relationships Under Equity Method Investments
Schedule of Equity Method Investments
Amortization period for tax deductible goodwill	15 years
Subsequent Event | Systematica Investment LP and Baring Private Equity Asia | Acquired Client Relationships Under Equity Method Investments
Schedule of Equity Method Investments
Acquired client relationships				$ 550

Equity Method Investments in 79

Equity Method Investments in Affiliates - Schedule of Financial Information for Affiliates Accounted for Under the Equity Method (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Equity Method Investments and Joint Ventures [Abstract]
Revenue	[1]	$ 2,217.1	$ 1,869.3	$ 1,589.6
Net income		431.5	253.8	$ 1,321.9
Assets	[2]	30,663.4	34,729.2
Liabilities and Non-controlling interest	[2]	$ 29,434.7	$ 33,048.6
[1]	Revenue includes advisory fees for asset management services and net investment income from consolidated investment partnerships.
[2]	Assets consist primarily of investment securities in consolidated investment partnerships, which are generally held by non-controlling interests.

Fixed Assets and Lease Commit80

Fixed Assets and Lease Commitments (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Fixed Assets and Lease Commitments [Abstract]
Consolidated rent expense	$ 36.3	$ 30.5	$ 30.3

Fixed Assets and Lease Commit81

Fixed Assets and Lease Commitments - Schedule of Fixed Assets (Details) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Fixed assets
Fixed assets, at cost	$ 231	$ 199.4
Accumulated depreciation and amortization	(116.9)	(104)
Fixed assets, net	114.1	95.4
Building and Leasehold Improvements
Fixed assets
Fixed assets, at cost	104.7	84.1
Software
Fixed assets
Fixed assets, at cost	45.4	40.8
Equipment
Fixed assets
Fixed assets, at cost	39.9	38.3
Furniture and Fixtures
Fixed assets
Fixed assets, at cost	22.4	17.5
Land and Improvements
Fixed assets
Fixed assets, at cost	$ 18.6	$ 18.7

Fixed Assets and Lease Commit82

Fixed Assets and Lease Commitments - Schedule of Aggregate Future Minimum Payments for Operating Leases (Details) $ in Millions	Dec. 31, 2015USD ($)
Operating Leased Assets [Line Items]
2,016	$ 36	[1]
2,017	33.7	[1]
2,018	31	[1]
2,019	29.5	[1]
2,020	28.4	[1]
Thereafter	82.1	[1]
Majority Shareholder
Operating Leased Assets [Line Items]
2,016	10.7
2,017	11
2,018	11
2,019	10.6
2,020	10.1
Thereafter	$ 38.7
[1]	The controlling interest portion is $10.7 million through 2016, $11.0 million each in 2017 and in 2018, $10.6 million in 2019, $10.1 million in 2020 and $38.7 million thereafter.

Payables and Accrued Liabilit83

Payables and Accrued Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Payables and Accruals [Abstract]
Accrued compensation and distributions	$ 455	$ 491.3
Unsettled fund share payables	76.6	78.3
Accrued income taxes	67.9	59.8
Accrued share repurchases	0	47.8
Accrued professional fees	31.4	26.9
Other	98.5	104.2
Accounts payable and accrued liabilities	$ 729.4	$ 808.3

Related Party Transactions (Det

Related Party Transactions (Details) - Prior Owner - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Other Liabilities
Related Party Transactions
Investment partnerships with prior owners	$ 75	$ 71.6
Non-Controlling Interests
Related Party Transactions
Investment partnerships with prior owners	$ 5.1	$ 13.5

Stockholders' Equity (Details)

Stockholders' Equity (Details) - $ / shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	May. 31, 2015
Stockholders' equity
Common stock, shares authorized (in shares)	153,000,000	153,000,000
Share repurchase activity
Shares repurchased (in shares)	1,700,000	1,200,000	100,000
Average price (in usd per share)	$ 209.39	$ 204.72	$ 184.89
Preferred Stock
Stockholders' equity
Preferred stock, shares authorized (in shares)	5,000,000
Common Stock
Share repurchase activity
Shares repurchased (in shares)	1,700,000	1,200,000	100,000
Average price (in usd per share)	$ 209.39	$ 204.72	$ 184.89
Voting Common Stock
Stockholders' equity
Common stock, shares authorized (in shares)	150,000,000
Share repurchase activity
Stock repurchase program, authorized amount (in shares)				3,000,000
Stock repurchase program, remaining shares authorized for repurchase (in shares)	2,300,000
Class B Non-Voting Common Stock
Stockholders' equity
Common stock, shares authorized (in shares)	3,000,000

Share-Based Compensation - Summ

Share-Based Compensation - Summary of Recent Share-Based Compensation Expense (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Share-based compensation expense	$ 34.2	$ 29.3	$ 27.5
Tax benefit	13.2	11.3	10.6
Cash received from stock options exercised	57.8	41.4
Tax benefit realized from exercise of stock options	44.5	60.2
Excess tax benefit from share-based compensation	44.5	61.5	$ 17.3
Total compensation cost not yet recognized	$ 70.6	$ 56.8
Weighted average period for recognition (in years)	3 years

Share-Based Compensation - Sche

Share-Based Compensation - Schedule of Transactions of the Company's Stock Options (Details) - Stock Options and Other Awards shares in Millions	12 Months Ended
	Dec. 31, 2015$ / sharesshares
Stock Options
Stock options outstanding at the beginning of the period (options) | shares	2.3
Options granted | shares	0
Options exercised | shares	(0.9)
Options forfeited | shares	0
Stock options outstanding at the end of the period (options) | shares	1.4
Exercisable stock options, at the end of the period (options) | shares	1.3
Weighted Average Exercise Price
Stock options outstanding, at the beginning of the period (in usd per option) | $ / shares	$ 83.42
Options granted | $ / shares	207.61
Options exercised | $ / shares	65.95
Options forfeited | $ / shares	101.29
Stock options outstanding, at the end of the period (in usd per option) | $ / shares	96.18
Exercisable stock options, at the end of the period (in usd per option) | $ / shares	$ 94.43
Weighted Average Remaining Contractual Life (years)
Stock options outstanding, at the end of the period (in years)	2 years 2 months 12 days
Exercisable stock options, at the end of the period (in years)	2 years 1 month 6 days

Share-Based Compensation - Stoc

Share-Based Compensation - Stock Options (Details) - Stock Options and Other Awards - USD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award
Fair value of stock options granted	$ 1	$ 0.6	$ 1
Intrinsic value of stock options exercised	130.2	$ 92.6	$ 77.4
Intrinsic value of exercisable options outstanding	$ 89
Options available for future grant under the Company's option plans (in shares)	3.5
Weighted average fair value of options granted (in usd per share)	$ 54.92	$ 60.20	$ 61.82
Minimum
Share-based Compensation Arrangement by Share-based Payment Award
Vesting Period	3 years
Expiration Period	7 years
Maximum
Share-based Compensation Arrangement by Share-based Payment Award
Vesting Period	5 years
Expiration Period	10 years

Share-Based Compensation - Sc89

Share-Based Compensation - Schedule of Assumptions Used to Determine Fair Value of Options Granted (Details) - Stock Options and Other Awards		12 Months Ended
		Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Assumptions used to determine fair value of options granted
Dividend yield		0.00%	0.00%	0.00%
Expected volatility	[1]	26.70%	29.70%	34.40%
Risk-free interest rate	[2]	1.50%	1.80%	1.50%
Expected life of options (in years)	[3]	5 years	5 years	5 years
Forfeiture rate	[3]	0.00%	0.00%	0.00%
[1]	ased on historical and implied volatility.
[2]	ased on the U.S. Treasury yield curve in effect at the date of grant.
[3]	ased on the Company’s historical data and expected exercise behavior.

Share-Based Compensation - Su90

Share-Based Compensation - Summary of Transactions of the Company's Restricted Stock (Details) - Restricted Stock - $ / shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2013
Restricted Stock
Units outstanding at the beginning of the period	400,000
Units granted	300,000	100,000
Units vested	(100,000)
Units forfeited	0
Units outstanding at the end of the period	600,000
Weighted Average Grant Date Value
Units outstanding at the beginning of the period (in dollars per share)	$ 182.83
Units granted	197.59
Units vested	174.19
Units forfeited	190.23
Units outstanding at the end of the period (in dollars per share)	$ 192.04

Share-Based Compensation - Rest

Share-Based Compensation - Restricted Stock (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award
Weighted average period for recognition (in years)	3 years
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award
Award fair value	$ 50.7	$ 8	$ 53.5
Vesting Period			6 years
Units granted	300,000		100,000
Market Condition 1			15.00%
Market Condition 2			25.00%
Market Condition 3			35.00%
Expected volatility			31.60%
Risk-free interest rate			2.00%
Dividend yield			0.00%
Weighted average period for recognition (in years)			4 years
Options available for future grant under the Company's option plans (in shares)	1,500,000
Restricted Stock | Minimum
Share-based Compensation Arrangement by Share-based Payment Award
Vesting Period	3 years
Restricted Stock | Maximum
Share-based Compensation Arrangement by Share-based Payment Award
Vesting Period	8 years

Affiliate Equity - Summary of A

Affiliate Equity - Summary of Affiliate Equity Expense (Recognized and Unrecognized) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Affiliate Equity
Non-controlling interest	$ 51.6	$ 37	$ 15.9
Total	62	66.2	50.6
Non-Controlling Interests
Affiliate Equity
Total	51.6	37	15.9
Unrecognized Affiliate Equity Expense
Non-Controlling Interest	$ 51.9	$ 41.6	$ 32.1
Remaining Life	5 years	6 years	7 years
Affiliate Partners
Affiliate Equity
Controlling interest	$ 16.9	$ 47.4	$ 56.4
Tax benefit	(6.5)	(18.2)	(21.7)
Controlling interest, net	10.4	29.2	34.7
Unrecognized Affiliate Equity Expense
Controlling Interest	$ 22.4	$ 29.5	$ 36.1
Remaining Life	3 years	3 years	3 years

Affiliate Equity - Schedule of

Affiliate Equity - Schedule of the Changes in Redeemable Non-controlling Interests (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Changes in redeemable non-controlling interests during the period
Beginning balance	$ 645.5	$ 641.9
Repurchases of redeemable Affiliate equity	(161.3)	(61.7)
Transfers from Non-controlling interests	49.5	22.7	$ 19.5
Changes in redemption value	81.6	43
Decrease attributable to consolidated products	(2.8)	(0.4)
Ending balance	$ 612.5	$ 645.5	$ 641.9

Afilliate Equity - Schedule of

Afilliate Equity - Schedule of the Effect of Changes in the Company's Ownership Interest in its Affiliates on the Controlling Interest's Equity (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Affiliate Equity [Abstract]
Net income (controlling interest)	$ 150.3	$ 109	$ 128.7	$ 128	$ 172.6	$ 103.2	$ 99.1	$ 77.2	$ 516	$ 452.1	$ 360.5
Increase in controlling interest paid-in capital related to Affiliate equity issuances									0.7	2.5	13.1
Decrease in controlling interest paid-in capital related to Affiliate equity repurchases									(89.8)	(35.8)	(87.1)
Net income attributable to controlling interest and transfers (to) or from Non-controlling interests									$ 426.9	$ 418.8	$ 286.5

Affiliate Equity (Details)

Affiliate Equity (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2015	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Affiliate Equity
Distributions paid to affiliate partners		$ 431.4	$ 569.4	$ 267.1
Payments to acquire interest in Affiliates		130.8	32.6	36.9
Issuance of interest in Affiliates		6.1	11	2.5
Proceeds from Collection of Advance to Affiliate		7.4	9.7	6.9
Total amount paid to affiliates		17.2	4.4	$ 5.5
Other Assets
Affiliate Equity
Due from Affiliates		22.6	20.8
Other Liabilities
Affiliate Equity
Due to Affiliates		$ 62.3	$ 29.3
Minimum
Affiliate Equity
Affiliate equity, conditional right to put interest, period	5 years
Maximum
Affiliate Equity
Affiliate equity, conditional right to put interest, period	15 years

Benefit Plans (Details)

Benefit Plans (Details) $ in Millions	12 Months Ended
	Dec. 31, 2015USD ($)plan	Dec. 31, 2014USD ($)	Dec. 31, 2013USD ($)
Compensation and Retirement Disclosure [Abstract]
Number of defined contribution plans | plan	3
Consolidated expenses related to benefit plans | $	$ 18.7	$ 17.2	$ 14.1

Income Taxes - Schedule of Inco

Income Taxes - Schedule of Income Tax Provision Attributable to Controlling and Non-Controlling Interests (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income tax provision
Current tax		$ 162.2	$ 165.1	$ 166.4
Deferred taxes		94.7	62.8	27.7
Provision for income taxes		$ 256.9	$ 227.9	$ 194.1
Effective tax rate attributable to controlling interests		32.80%	32.10%	33.90%
Parent
Income tax provision
Current tax		$ 152.4	$ 149.8	$ 153.1
Intangible-related deferred taxes		77.7	47.8	38.1
Other deferred taxes		21.2	15.8	(6.2)
Provision for income taxes		251.3	213.4	185
Income before income taxes (controlling interest)		$ 767.3	$ 665.5	$ 545.5
Effective tax rate attributable to controlling interests	[1]	32.80%	32.10%	33.90%
Non-Controlling Interests
Income tax provision
Current tax		$ 9.8	$ 15.3	$ 13.3
Deferred taxes		(4.2)	(0.8)	(4.2)
Provision for income taxes		$ 5.6	$ 14.5	$ 9.1
[1]	Taxes attributable to the controlling interest divided by Income before income taxes (controlling interest).

Income Taxes - Schedule of Cons

Income Taxes - Schedule of Consolidated Provision for Income Taxes (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Current:
Federal	$ 106.3	$ 93.8	$ 104.1
State	18.3	27.1	21.1
Foreign	37.6	44.2	41.2
Total current	162.2	165.1	166.4
Deferred:
Federal	97.9	72.5	38.1
State	14.2	1.1	8.9
Foreign	(17.4)	(10.8)	(19.3)
Total deferred	94.7	62.8	27.7
Provision for income taxes	$ 256.9	$ 227.9	$ 194.1

Income Taxes - Schedule of Comp

Income Taxes - Schedule of Components of Income before Income Taxes (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
Domestic	$ 827.6	$ 784.1	$ 604
International	263	229.5	259.7
Total	$ 1,090.6	$ 1,013.6	$ 863.7

Income Taxes - Schedule of Effe

Income Taxes - Schedule of Effective Income Tax Rate Computed Using Income before Income Taxes and Applying U.S. Federal Income Tax Rate (Details)		12 Months Ended
		Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income tax provision
Tax at U.S. federal income tax rate		35.00%	35.00%	35.00%
State income taxes, net of federal benefit(1)	[1]	2.60%	2.10%	2.80%
Effect of foreign operations		(3.50%)	(5.30%)	(2.50%)
Non-deductible expenses		(1.30%)	0.30%	(1.40%)
Effective tax rate attributable to controlling interests		32.80%	32.10%	33.90%
Parent
Income tax provision
Effective tax rate attributable to controlling interests	[2]	32.80%	32.10%	33.90%
Total effective income tax rate		23.60%	22.50%	22.50%
Non-Controlling Interests
Income tax provision
Effect of income from non-controlling interests		(9.20%)	(9.60%)	(11.40%)
[1]	State income taxes included changes related to state valuation allowances.
[2]	Taxes attributable to the controlling interest divided by Income before income taxes (controlling interest).

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Operating Loss Carryforwards [Line Items]
Deferred tax benefits from change in permanent status of foreign subsidiaries	$ 17.1	$ 30.3	$ 7.2
Deferred tax benefits from change in permanent status of foreign subsidiaries, resulting from current period		24.5	5.9
Deferred tax benefits from reinvestment of foreign earnings	5
Uncertain tax positions, increase based on prior years’ tax positions	1.6	10.8	0
Temporary difference due to repatriation of assets from a sale or liquidation of the subsidiary	188.1
Amount of deferred taxes not recognized	$ 71.1
State net operating loss carryforwards, expiration period	19 years
Foreign operating loss carryforwards, expiration period	20 years
Liability for uncertain tax positions including interest and related charges	$ 26.9	28.8	20.4
Accrued income tax interest and related charges	1.8	1.6	1.7
Unrecognized tax benefits that, if recognized, would affect effective tax rate	25.3	26.4	17.2
Decrease in uncertain tax positions from changes in foreign exchange rates	1.9
Foreign Tax Authority
Operating Loss Carryforwards [Line Items]
Deferred tax benefit due to re-valuation of deferred taxes from a change in enacted tax rates in the United Kingdom	10		11.2
Foreign Tax Authority | Non-Controlling Interests
Operating Loss Carryforwards [Line Items]
Deferred tax benefit due to re-valuation of deferred taxes from a change in enacted tax rates in the United Kingdom	$ 6.5		$ 7.6
State Tax Authority
Operating Loss Carryforwards [Line Items]
Uncertain tax positions, increase based on prior years’ tax positions		$ 8.4

Income Taxes - Schedule of C102

Income Taxes - Schedule of Components of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Deferred Tax Assets
Deferred compensation	$ 30.5	$ 26.8
State net operating loss carryforwards	17.1	15.2
Tax benefit of uncertain tax positions	14.6	16
Accrued expenses	4.4	19.6
Foreign loss carryforwards	12.3	11.5
Other	0	1.4
Total deferred tax assets	78.9	90.5
Valuation allowance	(20.5)	(18.4)
Deferred tax assets, net of valuation allowance	58.4	72.1
Deferred Tax Liabilities
Intangible asset amortization	(320.2)	(270.9)
Non-deductible intangible amortization	(109.8)	(126.4)
Convertible securities interest	(99.8)	(92.5)
Deferred income	(92.8)	(74)
Other	(1.5)	0
Total deferred tax liabilities	(624.1)	(563.8)
Net deferred tax liability	$ (565.7)	$ (491.7)

Income Taxes Income Taxes - Val

Income Taxes Income Taxes - Valuation Allowance (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Valuation Allowance [Line Items]
Increase (decrease) in valuation allowance, state net operating loss carryforward and realized deferred tax benefit		$ 6.5
Operating Loss Carryforwards
Valuation Allowance [Line Items]
Increase (decrease) in valuation allowance, state net operating loss carryforward and realized deferred tax benefit	$ (2.1)	2.5
Increase in State Uncertain Tax Positions
Valuation Allowance [Line Items]
Increase (decrease) in valuation allowance, state net operating loss carryforward and realized deferred tax benefit		(9.2)
State and Local Jurisdiction | Operating Loss Carryforwards
Valuation Allowance [Line Items]
Increase (decrease) in valuation allowance, state net operating loss carryforward and realized deferred tax benefit		$ 15.7

Income Taxes - Schedule of Reco

Income Taxes - Schedule of Reconciliation of Beginning and Ending Amount of Unrecognized Tax Benefits (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Reconciliation of beginning and ending amount of unrecognized tax benefits
Beginning balance	$ 28.8	$ 20.4	$ 22.6
Additions based on current year tax positions	2.2	2.6	4.1
Additions based on prior years’ tax positions	1.6	10.8	0
Reductions for prior years’ tax provisions	0	0	(0.1)
Reductions related to lapses of statutes of limitations	(4.3)	(4.1)	(5.4)
Additions (reductions) related to foreign exchange rates	1.4	0.9	0.8
Ending balance	$ 26.9	$ 28.8	$ 20.4

Earnings Per Share (Details)

Earnings Per Share (Details) - $ / shares shares in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Earnings Per Share [Abstract]
Shares repurchased (in shares)	1.7	1.2	0.1
Average price (in usd per share)	$ 209.39	$ 204.72	$ 184.89

Earnings Per Share - Schedule o

Earnings Per Share - Schedule of Reconciliation of the Numerator and Denominator used in the Calculation of Basic and Diluted Earnings per Share (Details) - USD ($) shares in Millions, $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Numerator
Net income (controlling interest)	$ 150.3	$ 109	$ 128.7	$ 128	$ 172.6	$ 103.2	$ 99.1	$ 77.2	$ 516	$ 452.1	$ 360.5
Interest expense on convertible securities, net of taxes									15.3	15.2	10.5
Net income (controlling interest), as adjusted									$ 531.3	$ 467.3	$ 371
Denominator
Average shares outstanding - basic (in shares)									54.3	55	53.1
Effect of dilutive instruments:
Stock options and other awards (in shares)									0.7	1.2	1.3
Forward sale (in shares)									0	0	0.3
Junior convertible securities (in shares)									2.2	2.2	2
Average shares outstanding - diluted (in shares)									57.2	58.4	56.7

Earnings Per Share - Diluted Ea

Earnings Per Share - Diluted Earnings per Share Calculations Excluding the Anti-dilutive Effect of Shares (Details) - shares shares in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Stock Options and Other Awards
Antidilutive Securities Excluded from Computation of Earnings Per Share
Antidilutive securities excluded from computation of earnings per share (in shares)	0	0	0.1
Senior Convertible Securities
Antidilutive Securities Excluded from Computation of Earnings Per Share
Antidilutive securities excluded from computation of earnings per share (in shares)	0	0	2.1
Junior Convertible Trust Preferred Securities
Antidilutive Securities Excluded from Computation of Earnings Per Share
Antidilutive securities excluded from computation of earnings per share (in shares)	0	0.4	2.2

Comprehensive Income - Summary

Comprehensive Income - Summary of the Tax Effects Allocated to each Component of Other Comprehensive Income (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Other Comprehensive Income (Loss), Pre-Tax
Foreign currency translation gain (loss)	$ (93.2)	$ (62)	$ (19.6)
Change in net realized and unrealized gain (loss) on derivative securities	2.3	0.6	1.5
Change in net unrealized gain (loss) on investment securities	34.8	5.6	19.5
Other comprehensive income (loss)	(56.1)	(55.8)	1.4
Other Comprehensive Income (Loss), Tax Benefit (Expense)
Foreign currency translation gain (loss)	0	0	0
Change in net realized and unrealized gain (loss) on derivative securities	(0.4)	(0.3)	(0.5)
Change in net unrealized gain (loss) on investment securities	(12.7)	(2.2)	(8)
Other comprehensive income (loss)	(13.1)	(2.5)	(8.5)
Other Comprehensive Income (Loss), Net of Tax
Foreign currency translation gain (loss)	(93.2)	(62)	(19.6)
Change in net realized and unrealized gain (loss) on derivative securities	1.9	0.3	1
Change in net unrealized gain (loss) on investment securities	22.1	3.4	11.5
Other comprehensive income (loss)	$ (69.2)	$ (58.3)	$ (7.1)

Comprehensive Income - Schedule

Comprehensive Income - Schedule of Components of Accumulated Other Comprehensive Income, Net of Taxes (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Accumulated Other Comprehensive Income (Loss) Net of Tax [Roll Forward]
Balance at the beginning of the period		$ 15.9	$ 74.2
Other comprehensive income (loss) before reclassifications		(78.9)	(60.4)
Amounts reclassified from other comprehensive income		9.7	2.1
Net other comprehensive income (loss)		(69.2)	(58.3)	$ (7.1)
Balance at the end of the period		(53.3)	15.9	74.2
Foreign Currency Translation Adjustment
Accumulated Other Comprehensive Income (Loss) Net of Tax [Roll Forward]
Balance at the beginning of the period		(5.4)	56.6
Other comprehensive income (loss) before reclassifications		(93.2)	(62)
Amounts reclassified from other comprehensive income		0	0
Net other comprehensive income (loss)		(93.2)	(62)
Balance at the end of the period		(98.6)	(5.4)	56.6
Realized and Unrealized Losses on Derivative Securities
Accumulated Other Comprehensive Income (Loss) Net of Tax [Roll Forward]
Balance at the beginning of the period		(1.6)	(1.9)
Other comprehensive income (loss) before reclassifications		0.8	0.3
Amounts reclassified from other comprehensive income		1.1	0
Net other comprehensive income (loss)		1.9	0.3
Balance at the end of the period		0.3	(1.6)	(1.9)
Unrealized Gain (Loss) on Investment Securities
Accumulated Other Comprehensive Income (Loss) Net of Tax [Roll Forward]
Balance at the beginning of the period	[1]	22.9	19.5
Other comprehensive income (loss) before reclassifications	[1]	13.5	1.3
Amounts reclassified from other comprehensive income	[1]	8.6	2.1
Net other comprehensive income (loss)	[1]	22.1	3.4
Balance at the end of the period	[1]	$ 45	$ 22.9	$ 19.5
[1]	See Note 2 for amounts reclassified from Other comprehensive income.

Selected Quarterly Financial110

Selected Quarterly Financial Data (Unaudited) - Schedule of Quarterly Results of Operations(Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Quarterly Financial Information Disclosure [Abstract]
Revenue	$ 589.8	$ 613.1	$ 646.6	$ 635	$ 641.2	$ 640.3	$ 636.3	$ 593.1	$ 2,484.5	$ 2,510.9	$ 2,188.8
Operating income	193.2	215.2	195.2	231.4	198.7	224.2	198.4	193.9	835	815.2	634.1
Income before income taxes	289.2	249.1	262	290.3	312.8	253.4	239.1	208.2	1,090.6	1,013.5	863.7
Net income (controlling interest)	$ 150.3	$ 109	$ 128.7	$ 128	$ 172.6	$ 103.2	$ 99.1	$ 77.2	$ 516	$ 452.1	$ 360.5
Earnings per share - diluted (in dollars per share)	$ 2.72	$ 1.98	$ 2.31	$ 2.27	$ 3.02	$ 1.82	$ 1.75	$ 1.40	$ 9.28	$ 8.01	$ 6.55

Segment Information (Details)

Segment Information (Details)	12 Months Ended
	Dec. 31, 2015segmentchannel	Dec. 31, 2014	Dec. 31, 2013
Segment Reporting [Abstract]
Number of operating segments | segment	3
Number of principal distribution channels | channel	3
Revenue attributable to clients domiciled outside the United States (as a percent)	40.00%	37.00%	38.00%

Segment Information - Schedule

Segment Information - Schedule of Segment Information (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Segment Reporting Information
Revenue	$ 589.8	$ 613.1	$ 646.6	$ 635	$ 641.2	$ 640.3	$ 636.3	$ 593.1	$ 2,484.5	$ 2,510.9	$ 2,188.8
Net income (controlling interest)	150.3	$ 109	$ 128.7	$ 128	172.6	$ 103.2	$ 99.1	$ 77.2	516	452.1	360.5
Total assets	7,784.8				7,698.1				7,784.8	7,698.1	6,318.8
Goodwill	2,668.4				2,652.8				2,668.4	2,652.8	2,341.7
Equity method investments in Affiliates	1,937.1				1,783.5				1,937.1	1,783.5	1,123.3
Institutional
Segment Reporting Information
Revenue									979.4	1,022.8	948.7
Net income (controlling interest)									229.3	227	219.9
Total assets	3,725.9				3,739.8				3,725.9	3,739.8	3,196.5
Goodwill	1,141.3				1,159.1				1,141.3	1,159.1	1,076.3
Equity method investments in Affiliates	1,609.3				1,533.8				1,609.3	1,533.8	942.6
Mutual Fund
Segment Reporting Information
Revenue									1,238.2	1,242.6	1,023
Net income (controlling interest)									229.7	180.1	103.4
Total assets	3,075.5				3,082				3,075.5	3,082	2,448.4
Goodwill	1,119.5				1,125.3				1,119.5	1,125.3	928.1
Equity method investments in Affiliates	185.7				150.3				185.7	150.3	77.7
High Net Worth
Segment Reporting Information
Revenue									266.9	245.5	217.1
Net income (controlling interest)									57	45	37.2
Total assets	983.4				876.3				983.4	876.3	673.9
Goodwill	407.6				368.4				407.6	368.4	337.3
Equity method investments in Affiliates	$ 142.1				$ 99.4				$ 142.1	$ 99.4	$ 103

Schedule II Valuation and Qu113

Schedule II Valuation and Qualifying Accounts (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Valuation Allowance
Reconciliation of beginning and ending balances of valuation and qualifying accounts
Balance at the beginning of the period		$ 18.4	$ 36.6	$ 21.3
Additions charged to costs and expenses		2.1	0	16.9
Additions charged to other accounts		0	0	0
Deductions		0	18.2	1.6
Balance at the end of the period		20.5	18.4	36.6
Other Allowances
Reconciliation of beginning and ending balances of valuation and qualifying accounts
Balance at the beginning of the period	[1]	12.1	8.8	8.4
Additions charged to costs and expenses	[1]	0.7	4.7	2.8
Additions charged to other accounts	[1]	0	0	0
Deductions	[1]	2.2	1.4	2.4
Balance at the end of the period	[1]	$ 10.6	$ 12.1	$ 8.8
[1]	Other Allowances represented reserves on notes received in connection with transfers of our interests in certain Affiliates as well as other receivable amounts, which we considered uncollectible.