Stagwell (STGW) 10-Q 8 Nov 16 2016 Q3 Quarterly report Financial data

Document And Entity Information

Document And Entity Information - shares	9 Months Ended
	Sep. 30, 2016	Oct. 31, 2016
Document Information [Line Items]
Entity Registrant Name	MDC PARTNERS INC
Entity Central Index Key	876,883
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Trading Symbol	MDCA
Document Type	10-Q
Document Period End Date	Sep. 30, 2016
Document Fiscal Year Focus	2,016
Document Fiscal Period Focus	Q3
Amendment Flag	false
Common Class A
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		54,063,007
Common Class B
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		3,755

CONDENSED CONSOLIDATED STATEMEN

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Share-based Compensation	$ 5,228	$ 3,266	$ 15,443	$ 13,025
Revenue:
Services	349,254	328,415	995,343	967,243
Operating Expenses:
Cost of services sold	235,659	212,925	675,940	648,386
Office and general expenses	83,303	78,786	233,840	206,169
Depreciation and amortization	11,412	13,086	34,068	39,393
Goodwill, Impairment Loss	29,631	0	29,631	0
Costs and Expenses, Total	360,005	304,797	973,479	893,948
Operating profit	(10,751)	23,618	21,864	73,295
Other Income (Expense):
Other, net	(6,008)	(15,623)	9,530	(29,315)
Interest expense and finance charges	(16,540)	(14,638)	(49,289)	(43,022)
Loss on redemption of notes	0	0	(33,298)	0
Interest income	218	114	599	338
Nonoperating Income (Expense), Total	(22,330)	(30,147)	(72,458)	(71,999)
Loss from continuing operations before income taxes and equity in earnings of non-consolidated affiliates	(33,081)	(6,529)	(50,594)	1,296
Income tax benefit	(540)	(1,191)	1,893	(566)
Loss from continuing operations before equity in earnings of non-consolidated affiliates	(32,541)	(5,338)	(52,487)	1,862
Equity in earnings of non-consolidated affiliates	70	172	9	627
Income from continuing operations	(32,471)	(5,166)	(52,478)	2,489
Loss from discontinued operations attributable to MDC Partners Inc., net of taxes	0	(1,316)	0	(6,281)
Net loss	(32,471)	(6,482)	(52,478)	(3,792)
Net income attributable to the noncontrolling interests	(1,059)	(2,122)	(3,172)	(7,343)
Net loss attributable to MDC Partners Inc.	$ (33,530)	$ (8,604)	$ (55,650)	$ (11,135)
Basic and Diluted
Loss from continuing operations attributable to MDC Partners Inc. common shareholders (usd per share)	$ (0.64)	$ (0.15)	$ (1.09)	$ (0.10)
Discontinued operations attributable to MDC Partners Inc. common shareholders (usd per share)	0	(0.02)	0	(0.12)
Net loss attributable to MDC Partners Inc. common shareholders (usd per share)	(0.64)	(0.17)	(1.09)	(0.22)
Income (Loss) from Continuing Operations, Per Diluted Share	$ (0.64)	$ (0.15)	$ (1.09)	$ (0.10)
Weighted Average Number of Common Shares Outstanding:
Basic (USD per share)	52,244,819	49,915,807	50,861,890	49,843,980
Diluted (USD per share)	52,244,819	49,915,807	50,861,890	49,843,980
Cost of Sales [Member]
Share-based Compensation	$ 3,026	$ 1,727	$ 10,393	$ 8,415
General and Administrative Expense [Member]
Share-based Compensation	$ 2,202	$ 1,539	$ 5,050	$ 4,610

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Comprehensive Loss
Net loss	$ (32,471)	$ (6,482)	$ (52,478)	$ (3,792)
Other comprehensive income (loss), net of applicable tax:
Foreign currency translation adjustment	(2,331)	(5,893)	8,354	(9,337)
Other comprehensive income (loss)	(30,140)	(589)	(60,832)	5,545
Other Comprehensive Income (Loss), Net of Tax	2,331	5,893	(8,354)	9,337
Comprehensive income (loss) attributable to noncontrolling interests	(569)	(344)	(4,481)	(3,409)
Comprehensive loss attributable to MDC Partners Inc.	$ (30,709)	$ (933)	$ (65,313)	$ 2,136

CONDENSED CONSOLIDATED BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Current Assets:
Cash and cash equivalents	$ 21,735	$ 61,458
Cash held in trust	5,268	5,122
Accounts receivable, less allowance for doubtful accounts of $1,465 and $1,306	419,355	361,044
Expenditures billable to clients	40,615	44,012
Other current assets	53,872	37,109
Total Current Assets	540,845	508,745
Fixed assets, at cost, less accumulated depreciation of $101,117 and $96,554	73,868	63,557
Investments in non-consolidated affiliates	5,159	6,263
Goodwill	868,483	870,301
Other intangible assets, net	92,975	72,382
Deferred tax asset	21,774	15,367
Other assets	39,208	41,010
Total Assets	1,642,312	1,577,625
Current Liabilities:
Accounts payable	331,330	359,568
Trust Liability, Current	5,268	5,122
Accruals and other liabilities	255,282	297,964
Advance billings	148,352	119,100
Current portion of long-term debt	260	470
Current portion of deferred acquisition consideration	119,506	130,400
Total Current Liabilities	859,998	912,624
Long-term debt, less current portion	951,187	728,413
Long-term portion of deferred acquisition consideration	123,591	216,704
Other liabilities	52,293	44,905
Deferred tax liabilities	106,950	92,581
Total Liabilities	2,094,019	1,995,227
Redeemable Noncontrolling Interests (Note 2)	60,174	69,471
Commitments, Contingencies and Guarantees (Note 11)
Shareholders’ Deficit:
Charges in excess of capital	(310,273)	(315,261)
Accumulated deficit	(582,640)	(526,990)
Total Shareholders' Deficit	(511,881)	(487,073)
Total Liabilities, Redeemable Noncontrolling Interests and Shareholders’ Deficit	1,642,312	1,577,625
Common Class A
Shareholders’ Deficit:
Class A Shares, no par value, unlimited authorized, 50,253,153 and 49,986,705 shares issued and outstanding in 2016 and 2015	315,368	269,841
Class B Shares, no par value, unlimited authorized, 3,755 shares issued and outstanding in 2016 and 2015, each convertible into one Class A share	315,368	269,841
Common Class B
Shareholders’ Deficit:
Class A Shares, no par value, unlimited authorized, 50,253,153 and 49,986,705 shares issued and outstanding in 2016 and 2015	1	1
Class B Shares, no par value, unlimited authorized, 3,755 shares issued and outstanding in 2016 and 2015, each convertible into one Class A share	1	1
Share Capital To Be Issued [Member]
Common Stock, Value, To be Issued	2,360
Shareholders’ Deficit:
Total Shareholders' Deficit		0
Share Capital To Be Issued [Member] | Common Class A
Common Stock, Value, To be Issued	2,360	0
AOCI Including Portion Attributable to Noncontrolling Interest [Member]
Shareholders’ Deficit:
Accumulated other comprehensive income (loss)	(3,406)	6,257
Total Shareholders' Deficit	(3,406)	6,257
Parent [Member]
Shareholders’ Deficit:
Stockholders' Equity Attributable to Parent	(578,590)	(566,152)
Total Shareholders' Deficit	(578,590)	(566,152)
Noncontrolling Interest [Member]
Shareholders’ Deficit:
Noncontrolling Interests	66,709	79,079
Total Shareholders' Deficit	$ 66,709	$ 79,079

CONDENSED CONSOLIDATED BALANCE5

CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Accounts receivable, allowance for doubtful accounts (in dollars)	$ 1,680	$ 1,306
Accumulated depreciation (in dollars)	$ 109,680	$ 96,554
Preferred stock, shares issued	0	0
Common Class A
Common stock, shares issued	52,724,504	49,986,705
Common stock, shares outstanding	52,724,504	49,986,705
Common Class B
Common stock, shares issued	3,755	3,755
Common stock, shares outstanding	3,755	3,755
Share Capital To Be Issued [Member]
Shares to be issued, shares	100,000
Share Capital To Be Issued [Member] | Common Class A
Shares to be issued, shares	100,000	0

CONDENSED CONSOLIDATED STATEME6

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($)	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Cash flows from operating activities:
Net loss	$ (52,478,000)	$ (3,792,000)
Loss from discontinued operations attributable to MDC Partners Inc., net of taxes	0	(6,281,000)
Loss from continuing operations	(52,478,000)	2,489,000
Adjustments to reconcile net loss from continuing operations to cash used in operating activities:
Stock-based compensation	15,443,000	13,025,000
Depreciation	16,853,000	13,666,000
Amortization of intangibles	17,215,000	25,727,000
Amortization of deferred finance charges and debt discount	8,736,000	1,702,000
Goodwill, Impairment Loss	29,631,000	0
Adjustment to deferred acquisition consideration	17,363,000	(3,866,000)
Deferred income tax	160,000	(1,020,000)
Gain (Loss) on Disposition of Assets	377,000	0
Earnings of non-consolidated affiliates	(9,000)	(627,000)
Other non-current assets and liabilities	1,853,000	3,930,000
Foreign exchange	(12,806,000)	24,739,000
Changes in working capital:
Accounts receivable	(47,767,000)	(63,134,000)
Expenditures billable to clients	5,551,000	(16,582,000)
Prepaid expenses and other current assets	(16,851,000)	(1,371,000)
Accounts payable, accruals and other liabilities	(94,887,000)	(84,000)
Advance billings	25,824,000	(7,741,000)
Net Cash Provided by (Used in) Operating Activities, Continuing Operations	(58,919,000)	(9,147,000)
Discontinued operations	0	(1,342,000)
Net cash used in operating activities	(58,919,000)	(10,489,000)
Cash flows used in investing activities:
Capital expenditures	(19,723,000)	(17,665,000)
Acquisitions, net of cash acquired	2,531,000	(21,050,000)
Proceeds from sale of assets	215,000	21,000
Other investments	(2,571,000)	(6,507,000)
Distributions from non-consolidated affiliates	4,885,000	2,478,000
Cash flows used in continuing investing activities	(14,663,000)	(42,723,000)
Discontinued operations	0	17,101,000
Net cash used in investing activities	(14,663,000)	(25,622,000)
Cash flows provided by financing activities:
Payments for (Proceeds from) Previous Acquisition	(129,616,000)	(132,997,000)
Repayment of long-term debt	(381,000)	(397,000)
Purchase of shares	(2,798,000)	(1,792,000)
Premium Paid On Redemption Of Notes	(26,873,000)	0
Payments of Financing Costs	(21,569,000)	0
Distributions to noncontrolling interests	(6,549,000)	(9,462,000)
Cash overdrafts	17,532,000	27,207,000
Payment of dividends	(32,580,000)	(31,692,000)
Cash flows provided by continuing financing activities	32,663,000	(63,633,000)
Discontinued operations	0	(40,000)
Net cash provided by financing activities	32,663,000	(63,673,000)
Effect of exchange rate changes on cash and cash equivalents	1,196,000	2,194,000
Decrease in cash and cash equivalents	(39,723,000)	(97,590,000)
Cash and cash equivalents at beginning of period	61,458,000	113,348,000
Cash and cash equivalents at end of period	21,735,000	15,758,000
Supplemental disclosures:
Cash income taxes paid	2,798,000	1,400,000
Cash interest paid	27,979,000	26,358,000
Change in assets held-in-trust	147,000	(752,000)
Non-cash transactions:
Capital leases	0	106,000
Dividends payable	1,077,000	1,615,000
Leasehold improvements financed by landlord	7,250,000	0
Six Point Seven Five Percentage Notes [Member]
Adjustments to reconcile net loss from continuing operations to cash used in operating activities:
Loss on redemption of notes	26,873,000	0
Cash flows provided by financing activities:
Proceeds from Issuance of Senior Long-term Debt	900,000,000	0
Repayments of Senior Debt	735,000,000	0
Wells Fargo Capital Finance, LLC | Revolving Credit Facility [Member]
Cash flows provided by financing activities:
Repayments of Lines of Credit	(1,255,608,000)	(447,973,000)
Proceeds from (Repayments of) Lines of Credit	1,326,105,000	533,249,000
Common Class A [Member] | Common Stock [Member]
Non-cash transactions:
Stock Issued During Period, Value, New Issues	10,458,000	0
Common Class A [Member] | Forsman & Bodenfors AB [Domain] | Common Stock [Member]
Non-cash transactions:
Stock Issued During Period, Value, Acquisitions	$ 34,219,000	$ 0

CONDENSED STATEMENTS OF SHAREHO

CONDENSED STATEMENTS OF SHAREHOLDERS' DEFICIT - USD ($) $ in Thousands	Total	Common StockCommon Class A	Common StockCommon Class B	Share Capital To Be Issued [Member]	Share Capital To Be Issued [Member]Common Class A	Additional Paid-in Capital	Charges in Excess of Capital	Accumulated Deficit	Accumulated Other Comprehensive Income (Loss)	Parent [Member]	Noncontrolling Interest [Member]	Contingent Consideration, Liability Settlements [Domain]	Contingent Consideration, Liability Settlements [Domain]Parent [Member]	Contingent Consideration Classified as Equity [Member]	Contingent Consideration Classified as Equity [Member]Parent [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common Stock, Shares, To be Issued					0
Common Stock, Value, To be Issued					$ 0
Balance at Dec. 31, 2015	$ (487,073)	$ 269,841	$ 1	$ 0		$ 0	$ (315,261)	$ (526,990)	$ 6,257	$ (566,152)	$ 79,079
Balance (in shares) at Dec. 31, 2015		49,986,704.5	3,754.5
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss attributable to MDC Partners Inc.	(55,650)							(55,650)		(55,650)	0
Other Comprehensive income (loss)	(8,354)	$ 0	0	0		0	0	0	(9,663)	(9,663)	1,309
Stock Issued During Period, Restricted Stock and Stock Options, Net of Forfeitures		283,290
Stock Issued During Period, Value, Restricted Stock and Stock Options, Net of Forfeitures		$ 3,648
Issuance of restricted stock	0		$ 0	$ 0		(3,648)	0	0	0	0	0
Stock Issued During Period, Shares, New Issues		691,559
Stock Issued During Period, Value, New Issues		$ 10,458										$ 12,818	$ 12,818
Stock Issued During Period, Value, Acquisitions														$ 34,219	$ 34,219
Stock Authorized During Period, Shares, To be Issued					100,000
Stock Authorized During Period, Value, To be Issued					$ 2,360
Issuance of restricted stock (in shares)			0	0
Shares acquired and cancelled	(2,798)	$ (2,798)	$ 0	$ 0		0	0	0	0	(2,798)	0
Shares acquired and cancelled (in shares)		(137,050)	0	0
Stock-based compensation	8,259	$ 0	$ 0	$ 0		8,259	0	0	0	8,259	0
Changes in redemption value of redeemable noncontrolling interests		0	0	0			0	0	0		0
Temporary Equity, Accretion to Redemption Value	10,626					10,626				10,626
Noncontrolling Interest, Increase from Business Combination	8,819					22,498				22,498	(13,679)
Changes in noncontrolling interests and redeemable noncontrolling interest from step-up transactions										22,498
Dividends paid and to be paid	(32,747)	0	0	0		(32,747)	0	0	0	(32,747)	0
Transfer to charges in excess of capital	0	0	0	$ 0		(4,988)	4,988	0	0	0	0
Balance at Sep. 30, 2016	$ (511,881)	$ 315,368	$ 1			$ 0	$ (310,273)	$ (582,640)	$ (3,406)	$ (578,590)	$ 66,709
Balance (in shares) at Sep. 30, 2016		52,724,504	3,755
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common Stock, Shares, To be Issued				100,000	100,000
Common Stock, Value, To be Issued				$ 2,360	$ 2,360

Basis of Presentation

Basis of Presentation	9 Months Ended
	Sep. 30, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	1. Basis of Presentation MDC Partners Inc. (the “Company” or “MDC”) has prepared the unaudited condensed consolidated interim financial statements included herein pursuant to the rules and regulations of the United States Securities and Exchange Commission (the “SEC”). Certain information and footnote disclosures normally included in annual financial statements prepared in accordance with generally accepted accounting principles (“GAAP”) of the United States of America (“U.S. GAAP”) have been condensed or omitted pursuant to these rules. The accompanying financial statements reflect all adjustments, consisting of normally recurring accruals, which in the opinion of management are necessary for a fair presentation, in all material respects, of the information contained therein. Results of operations for interim periods are not necessarily indicative of annual results. During the third quarter of 2016, the Company changed its Reportable segment to coincide with the new reporting structure. Prior year results have been recast to reflect the new segment reporting. References herein to “Partner Firms” generally refer to the Company's subsidiary agencies. These statements should be read in conjunction with the consolidated financial statements and related notes included in the Annual Report on Form 10-K for the year ended December 31, 2015 .

Significant Accounting Policies

Significant Accounting Policies	9 Months Ended
	Sep. 30, 2016
Accounting Policies [Abstract]
Significant Accounting Policies	2. Significant Accounting Policies The Company’s significant accounting policies are summarized as follows: Accounting Change. On January 1, 2016, the Company retrospectively adopted the Financial Accounting Standards Board (the “FASB”) Accounting Standards Update (“ASU”) 2015-03, Interest - Imputation of Interest. This update requires that debt issuance costs related to a recognized debt liability be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability. As a result of the adoption of this update, the balance sheet at December 31, 2015 and September 30, 2015 was adjusted to reflect the reclassification of $12,625 and $13,254 , respectively, from other assets to long-term debt. Principles of Consolidation . The accompanying condensed consolidated financial statements include the accounts of MDC Partners Inc. and its domestic and international controlled subsidiaries that are not considered variable interest entities, and variable interest entities for which the Company is the primary beneficiary. Intercompany balances and transactions have been eliminated in consolidation. Reclassifications . Certain reclassifications have been made to the prior period financial statements to conform to the current period presentation. Use of Estimates. The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions. These estimates and assumptions affect the reported amounts of assets and liabilities including goodwill, intangible assets, contingent deferred acquisition consideration, valuation allowances for receivables, deferred tax assets and the amounts of revenue and expenses reported during the period. These estimates are evaluated on an ongoing basis and are based on historical experience, current conditions and various other assumptions believed to be reasonable under the circumstances. Actual results could differ from these estimates. Fair Value. The Company applies the fair value measurement guidance of the FASB Accounting Standards Codification (the “ASC”) Topic 820, Fair Value Measurements, for financial assets and liabilities that are required to be measured at fair value and for non-financial assets and liabilities that are not required to be measured at fair value on a recurring basis, including goodwill and other identifiable intangible assets. The measurement of fair value requires the use of techniques based on observable and unobservable inputs. Observable inputs reflect market data obtained from independent sources, while unobservable inputs reflect market assumptions. The inputs create the following fair value hierarchy: • Level 1 - Quoted 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 where inputs are observable or where significant value drivers are observable. • Level 3 - Instruments where significant value drivers are unobservable to third parties. When available, the Company uses quoted market prices to determine the fair value of its financial instruments and classifies such items in Level 1. In some cases, quoted market prices are used for similar instruments in active markets and the Company classifies such items in Level 2. Concentration of Credit Risk. The Company provides marketing communications services to clients who operate in most industry sectors. Credit is granted to qualified clients in the ordinary course of business. Due to the diversified nature of the Company’s client base, the Company does not believe that it is exposed to a concentration of credit risk. No client accounted for more than 10% of the Company’s consolidated accounts receivable at September 30, 2016 and December 31, 2015 . No clients accounted for 10% of the Company’s revenue for the three and nine months ended September 30, 2016 or for the three and nine months ended September 30, 2015 . Cash and Cash Equivalents. The Company’s cash equivalents are primarily comprised of investments in overnight interest-bearing deposits, commercial paper and money market instruments and other short-term investments with original maturity dates of three months or less at the time of purchase. The Company has a concentration of credit risk in that there are cash deposits in excess of federally insured amounts. Cash in Trust. A subsidiary of the Company holds restricted cash in trust accounts related to funds received on behalf of clients. Such amounts are held in escrow under depositary service agreements and distributed at the direction of the clients. The funds are presented as a corresponding liability on the balance sheet. Allowance for Doubtful Accounts . Trade receivables are stated at invoiced amounts less allowances for doubtful accounts. The allowances represent estimated uncollectible receivables associated with potential customer defaults usually due to customers’ potential insolvency. The allowances include amounts for certain customers where a risk of default has been specifically identified. The assessment of the likelihood of customer defaults is based on various factors, including the length of time the receivables are past due, historical experience and existing economic conditions. Expenditures Billable to Clients . Expenditures billable to clients consist principally of outside vendor costs incurred on behalf of clients when providing advertising, marketing and corporate communications services that have not yet been invoiced to clients. Such amounts are invoiced to clients at various times over the course of the production process. Fixed Assets . Fixed assets are stated at cost, net of accumulated depreciation. Computers, furniture and fixtures are depreciated on a straight-line basis over periods of three to seven years. Leasehold improvements are depreciated on a straight-line basis over the lesser of the term of the related lease or the estimated useful life of the asset. Repairs and maintenance costs are expensed as incurred. Equity Method Investments. The equity method is used to account for investments in entities in which the Company has an ownership interest of less than 50% and has significant influence, or joint control by contractual arrangement, (i) over the operating and financial policies of the affiliate or (ii) has an ownership interest greater than 50% ; however, the substantive participating rights of the noncontrolling interest shareholders preclude the Company from exercising unilateral control over the operating and financial policies of the affiliate. The Company’s investments accounted for using the equity method include a 30% undivided interest in a real estate joint venture and various interests in investment funds. The Company’s management periodically evaluates these investments to determine if there has been a decline in value that is other than temporary. These investments are included in investments in non-consolidated affiliates. Cost Method Investments. From time to time, the Company makes non-material cost based investments in start-up advertising technology companies and innovative consumer product companies where the Company does not exercise significant influence over the operating and financial policies of the investee. The total net cost basis of these investments, which is included in other assets on the balance sheet, at September 30, 2016 and December 31, 2015 was $10,607 and $11,763 , respectively. These investments are periodically evaluated to determine whether a significant event or change in circumstances has occurred that may impact the fair value of each investment other than temporary declines below book value. A variety of factors are considered when determining if a decline is other than temporary, including, among others, the financial condition and prospects of the investee, as well as the Company’s investment intent. In addition, the Company’s partner agencies may receive minority equity interests from start-up companies in lieu of fees. Business Combinations. Business combinations are accounted for using the acquisition method and accordingly, the assets acquired (including identified intangible assets), the liabilities assumed and any noncontrolling interest in the acquired business are recorded at their acquisition date fair values. The Company’s acquisition model typically provides for an initial payment at closing and for future additional contingent purchase price obligations. Contingent purchase price obligations are recorded as deferred acquisition consideration on the balance sheet at the acquisition date fair value and are remeasured at each reporting period. Changes in such estimated values are recorded in the results of operations. For further information see Note 4 and Note 9. For the three and nine months ended September 30, 2016 and 2015 , $11,152 and $17,180 of expense, respectively, and $4,928 of expense and $5,566 of income, respectively, related to changes in such estimated values was recorded in results of operations. The Company expenses acquisition related costs. For the three and nine months ended September 30, 2016 and 2015 , $806 and $2,266 , respectively, and $728 and $2,444 , respectively, of acquisition related costs were charged to operations. For each acquisition, the Company undertakes a detailed review to identify intangible assets and a valuation is performed for all such identified assets. The Company uses several market participant measurements to determine the estimated value. This approach includes consideration of similar and recent transactions, as well as utilizing discounted expected cash flow methodologies. Like most service businesses, a substantial portion of the intangible asset value that the Company acquires is the specialized know-how of the workforce, which is treated as part of goodwill and is not required to be valued separately. The majority of the value of the identifiable intangible assets acquired is derived from customer relationships, including the related customer contracts, as well as trade names. In executing the Company’s overall acquisition strategy, one of the primary drivers in identifying and executing a specific transaction is the existence of, or the ability to, expand the existing client relationships. The expected benefits of the Company’s acquisitions are typically shared across multiple agencies and regions. Goodwill and Impairment of Goodwill. The Company reviews goodwill and other intangible assets with indefinite lives not subject to amortization for impairment annually as of October 1 st of each year or more frequently if indicators of potential impairment exist. For goodwill, impairment is assessed at the reporting unit level. During the third quarter of 2016 the Company changed its operating segments, as a result of the management structure change as discussed in Note 11, which resulted in a corresponding change to the Company’s reporting units. Each Partner Firm now represents an operating segment as well as a reporting unit for goodwill impairment testing. Due to triggering events during the third quarter of 2016 interim goodwill impairment testing was performed which resulted in an impairment of goodwill charge of approximately $29,631 . In addition, the Company sold all of its ownership interests in Bryan Mills Iradesso Corporation (“Bryan Mills”) to the noncontrolling shareholders, resulting in a write off of goodwill of $764 . See Note 8 for further information. Redeemable Noncontrolling Interests . Many of the Company’s acquisitions include contractual arrangements where the noncontrolling shareholders have an option to purchase, or may require the Company to purchase, such noncontrolling shareholders’ incremental ownership interests under certain circumstances and the Company has similar call options under the same contractual terms. The amount of consideration under these contractual arrangements is not a fixed amount, but rather is dependent upon various valuation formulas as described in Note 12. In the event that an incremental purchase may be required of the Company, the amounts are recorded as redeemable noncontrolling interests in mezzanine equity on the balance sheet at their acquisition date fair value and adjusted for changes to their estimated redemption value through additional paid-in capital (but not less than their initial redemption value), except for foreign currency translation adjustments. These adjustments will not impact the calculation of earnings (loss) per share if the redemption values are less than the estimated fair values. For the three and nine months ended September 30, 2016 and 2015 , there was no impact on the Company's earnings (loss) per share calculation. Changes in the estimated redemption amounts of the redeemable noncontrolling interests are adjusted at each reporting period with a corresponding adjustment to equity. These adjustments will not impact the calculation of earnings (loss) per share. The following table presents changes in redeemable noncontrolling interests: Nine Months Ended September 30, 2016 Year Ended December 31, 2015 Beginning Balance $ 69,471 $ 194,951 Redemptions (890 ) (155,042 ) Additions (1) 2,274 7,703 Changes in redemption value (10,626 ) 22,809 Currency Translation Adjustments (55 ) (950 ) Ending Balance $ 60,174 $ 69,471 (1) Additions consist of transfers from noncontrolling interests related to step-up transactions and new acquisitions. Subsidiary and Equity Investment Stock Transactions. Transactions involving the purchase, sale or issuance of stock of a subsidiary where control is maintained are recorded as a reduction in the redeemable noncontrolling interests or noncontrolling interests, as applicable. Any difference between the purchase price and noncontrolling interest are recorded to additional paid-in capital. In circumstances where the purchase of shares of an equity investment results in obtaining control, the existing carrying value of the investment is remeasured to the acquisition date fair value and any gain or loss is recognized in results of operations. Variable Interest Entity . Effective March 28, 2012, the Company invested in Doner Partners LLC (“Doner”). The Company acquired a 30% voting interest and convertible preferred interests that allow the Company to increase ordinary voting ownership to 70% at the Company’s option. The Company has determined that (i) this entity is a variable interest entity, and (ii) the Company is the primary beneficiary because it receives a disproportionate share of profits and losses as compared to its ownership percentage. As such, Doner is consolidated for all periods subsequent to the date of investment. Doner is a full service integrated creative agency that is included as part of the Company’s portfolio in the Reportable segment. The Company’s Credit Agreement (see Note 7) is guaranteed and secured by all of Doner’s assets. Total assets and total liabilities of Doner included in the Company’s consolidated balance sheet at September 30, 2016 were $99,047 and $52,381 , respectively, and at December 31, 2015 were $122,558 and $86,047 , respectively. Guarantees . Guarantees issued or modified by the Company to third parties after January 1, 2003 are generally recognized at the inception or modification of the guarantee as a liability for the obligations it has undertaken in issuing the guarantee, including its ongoing obligation to stand ready to perform over the term of the guarantee in the event that the specified triggering events or conditions occur. The initial measurement of that liability is the fair value of the guarantee. The recognition of a liability is required even if it is not probable that payments will be required under a guarantee. The Company’s liability associated with guarantees is not significant. (See Note 12.) Revenue Recognition. The Company’s revenue recognition policies are established in accordance with the Revenue Recognition topics of the FASB ASC, and accordingly, revenue is recognized when all of the following criteria are satisfied: (i) persuasive evidence of an arrangement exists; (ii) the selling price is fixed or determinable; (iii) services have been performed or upon delivery of the products when ownership and risk of loss has transferred to the client; and (iv) collection of the resulting receivable is reasonably assured. The Company follows the Multiple-Element Arrangement topic of the FASB ASC, which addresses certain aspects of the accounting by a vendor for arrangements under which it will perform multiple revenue-generating activities and how to determine whether an arrangement involving multiple deliverables contains more than one unit of accounting. The Company follows the Principal Agent Consideration topic of the FASB ASC which addresses (i) whether revenue should be recorded at the gross amount billed because it has earned revenue from the sale of goods or services, or recorded at the net amount retained because it has earned a fee or commission, and (ii) that reimbursements received for out-of-pocket expenses incurred should be characterized in the income statement as revenue. Accordingly, the Company has included such reimbursed expenses in revenue. The Company earns revenue from agency arrangements in the form of retainer fees or commissions; from short-term project arrangements in the form of fixed fees or per diem fees for services; and from incentives or bonuses. Non-refundable retainer fees are generally recognized on a straight-line basis over the term of the specific customer arrangement. Commission revenue is earned and recognized upon the placement of advertisements in various media when the Company has no further performance obligations. Fixed fees for services are recognized upon completion of the earnings process and acceptance by the client. Per diem fees are recognized upon the performance of the Company’s services. In addition, for a limited number of certain service transactions, which require delivery of a number of service acts, the Company uses the proportional performance model, which generally results in revenue being recognized based on the straight-line method. Fees billed to clients in excess of fees recognized as revenue are classified as Advanced Billings on the Company’s balance sheet. A small portion of the Company’s contractual arrangements with customers includes performance incentive provisions, which allow the Company to earn additional revenue as a result of its performance relative to both quantitative and qualitative goals. The Company recognizes the incentive portion of revenue under these arrangements when specific quantitative goals are assured, or when the Company’s clients determine performance against qualitative goals has been achieved. In all circumstances, revenue is only recognized when collection is reasonably assured. The Company records revenue net of sales and other taxes due to be collected and remitted to governmental authorities. Cost of Services Sold . Cost of services sold do not include depreciation charges for fixed assets. Interest Expense . Interest expense primarily consists of the cost of borrowing on the Company’s previously outstanding 6.75% senior notes due 2020 (the “6.75% Notes”); the Company’s 6.50% senior unsecured notes due 2024 (the “6.50% Notes”); and the Company’s $325 million senior secured revolving credit agreement due 2021 (the “Credit Agreement”). The Company uses the effective interest method to amortize the deferred financing costs on the 6.75% Notes and the 6.50% Notes as well as the original issue premium on the 6.75% Notes. The Company also uses the straight-line method to amortize the deferred financing costs on the Credit Agreement. For the three and nine months ended September 30, 2016 and 2015 , interest expense included $30 and $181 , respectively, and $770 and $1,700 , respectively, relating to present value adjustments for fixed deferred acquisition consideration payments. The Company redeemed the 6.75% Notes with the net proceeds from the issuance of the 6.50% Notes. For further information see Note 7. Income Taxes. The Company’s U.S. operating units are generally structured as limited liability companies, which are treated as partnerships for tax purposes. The Company is only taxed on its share of the profits, while noncontrolling holders are responsible for taxes on their share of the profits. The Company currently has a fully reserved valuation allowance on its deferred tax assets related to U.S. net operating losses. During the nine months ended September 30, 2016 and 2015 , the Company’s effective tax rate was lower than the statutory rate due primarily to losses in certain tax jurisdictions where a valuation allowance was deemed necessary. Stock-Based Compensation. Under the fair value method, compensation cost is measured at fair value at the date of grant and is expensed over the service period, in this case the award’s vesting period. When awards are exercised, share capital is credited by the sum of the consideration paid, together with the related portion previously credited to additional paid-in capital when compensation costs were charged against income or acquisition consideration. The Company uses its historical volatility derived over the expected term of the award to determine the volatility factor used in determining the fair value of the award. Stock-based awards that are settled in cash, or may be settled in cash at the option of employees, are recorded as liabilities. The measurement of the liability and compensation cost for these awards is based on the fair value of the award, and is recorded in operating income over the service period, in this case the award’s vesting period. Changes in the Company’s payment obligation prior to the settlement date of a stock-based award are recorded as compensation cost in operating income in the period of the change. The final payment amount for such awards is established on the date of the exercise of the award by the employee. Stock-based awards that are settled in cash or equity at the option of the Company are recorded at fair value on the date of grant and recorded as additional paid-in capital. The fair value measurement of the compensation cost for these awards is based on using the Black-Scholes option pricing-model and is recorded in operating income over the service period, in this case the award’s vesting period. It is the Company’s policy for issuing shares upon the exercise and/or vesting of an equity incentive award to calculate and verify the amount of shares to be issued, as well as the amount of proceeds to be collected (if any) and to deliver new shares to the exercising party. The Company has adopted the straight-line attribution method for determining the compensation cost to be recorded during each accounting period. However, awards based on performance conditions are recorded as compensation expense when the performance conditions are expected to be met. The Company treats benefits paid by shareholders or equity members to employees as a stock-based compensation charge with a corresponding credit to additional paid-in-capital. From time to time, certain acquisitions and step-up transactions include an element of compensation related payments. The Company accounts for those payments as stock-based compensation. During the nine months ended September 30, 2016 , the Company issued 296,000 shares of restricted stock and restricted stock units (collectively, “RSUs”) to its employees and directors. The RSUs have an aggregate grant date fair value of $4,454 and generally vest on the third anniversary of the date of grant. In addition, the Company awarded RSUs of which 523,321 awarded shares were outstanding as of September 30, 2016 . The vesting of these awards are contingent upon the Company meeting a cumulative three year earnings target and continued employment through the vesting date. Once the Company defines the earnings target, the grant date is established and the Company will record the compensation expense over the vesting period. A total of 1,404,081 Class A shares of RSUs, granted to employees as equity incentive awards but not yet vested, has been excluded in the Company’s calculation of Class A shares outstanding as of September 30, 2016 . Loss per Common Share . Basic loss per share is based upon the weighted average number of common shares outstanding during each period. “Share capital to be issued” as reflected in Shareholders’ Equity on the balance sheet are also included if there is no circumstance under which those shares would not be issued. Diluted income per share is based on the above, in addition, if dilutive, it also includes common share equivalents, which include outstanding options, stock appreciation rights, and unvested restricted stock units. Foreign Currency Translation . The Company’s financial statements were prepared in accordance with the requirements of the Foreign Currency Translation topic of the FASB ASC. The functional currency of the Company is the Canadian dollar and it has decided to use U.S. dollars as its reporting currency for consolidated reporting purposes. Generally, the Company’s subsidiaries use their local currency as their functional currency. Accordingly, the currency impacts of the translation of the balance sheets of the Company’s non-U.S. dollar based subsidiaries to U.S. dollar statements are included as cumulative translation adjustments in accumulated other comprehensive income. Translation of intercompany debt, which is not intended to be repaid, is included in cumulative translation adjustments. Cumulative translation adjustments are not included in net earnings unless they are actually realized through a sale or upon complete or substantially complete liquidation of the Company’s net investment in the foreign operation. Translation of current intercompany balances are included in net earnings. The balance sheets of non-U.S. dollar based subsidiaries are translated at the period end rate. The income statements of non-U.S. dollar based subsidiaries are translated at average exchange rates for the period. Gains and losses arising from the Company’s foreign currency transactions are reflected in net earnings. Unrealized gains or losses arising on the translation of certain intercompany foreign currency transactions that are of a long-term nature (that is settlement is not planned or anticipated in the future) are included as cumulative translation adjustments in accumulated other comprehensive income.

Loss Per Common Share

Loss Per Common Share	9 Months Ended
	Sep. 30, 2016
Earnings Per Share [Abstract]
Loss Per Common Share	3. Loss Per Common Share The following table sets forth the computation of basic and diluted loss per common share from continuing operations. Three Months Ended Nine Months Ended 2016 2015 2016 2015 Numerator Numerator for basic loss per common share - income (loss) from continuing operations $ (32,471 ) $ (5,166 ) $ (52,478 ) $ 2,489 Net income attributable to the noncontrolling interests (1,059 ) (2,122 ) (3,172 ) (7,343 ) Net loss from continuing operations attributable to MDC Partners Inc. common shareholders (33,530 ) (7,288 ) (55,650 ) (4,854 ) Effect of dilutive securities — — — — Numerator for diluted loss per common share - loss attributable to MDC Partners Inc. common shareholders from continuing operations $ (33,530 ) $ (7,288 ) $ (55,650 ) $ (4,854 ) Denominator Denominator for basic loss per common share - weighted average common shares 52,244,819 49,915,807 50,861,890 49,843,980 Effect of dilutive securities — — — — Denominator for diluted loss per common share - adjusted weighted shares and assumed conversions 52,244,819 49,915,807 50,861,890 49,843,980 Basic loss per common share from continuing operations $ (0.64 ) $ (0.15 ) $ (1.09 ) $ (0.10 ) Diluted loss per common share from continuing operations $ (0.64 ) $ (0.15 ) $ (1.09 ) $ (0.10 ) During the three and nine months ended September 30, 2016 , options and other rights to purchase 918,260 shares of common stock, which includes 880,760 shares of non-vested restricted stock and restricted stock units, were outstanding and were excluded in the computation of diluted income per common share. The remaining contingent non-vested restricted stock and restricted stock units of 523,321 shares are also excluded from the diluted calculation since the contingency has not been met at September 30, 2016 . During the three and nine months ended September 30, 2015 , options and other rights to purchase 942,574 shares of common stock, which includes 867,574 shares of non-vested restricted stock, were outstanding and were excluded in the computation of diluted income per common share.

Acquisitions

Acquisitions	9 Months Ended
	Sep. 30, 2016
Business Combinations [Abstract]
Acquisitions	4. Acquisitions Valuations of acquired companies are based on a number of factors, including specialized know-how, reputation, competitive position and service offerings. The Company’s acquisition strategy has been focused on acquiring the expertise of an assembled workforce in order to continue to build upon the core capabilities of its various strategic business platforms to better serve the Company’s clients. MDC’s strategy includes acquiring ownership stakes in well-managed businesses with strong reputations in the industry. The Company’s model of “Perpetual Partnership” often involves acquiring a majority interest rather than a 100% interest and leaving management owners with a significant financial interest in the performance of the acquired entity for a minimum period of time, typically not less than five years. The Company’s acquisition model in this scenario typically provides for (i) an initial payment at the time of closing, (ii) additional contingent purchase price obligations based on the future performance of the acquired entity, and (iii) an option by the Company to purchase (and in some instances a requirement to so purchase) the remaining interest of the acquired entity under a predetermined formula. Contingent purchase price obligations. The Company’s contingent purchase price obligations are generally payable within a five year period following the acquisition date, and are based on (i) the achievement of specific thresholds of future earnings, and (ii) in certain cases, the growth rate of those earnings. Contingent purchase price obligations are recorded as deferred acquisition consideration on the balance sheet at the acquisition date fair value and adjusted at each reporting period through operating income or net interest expense, depending on the nature of the arrangement. On occasion, the Company may initiate a renegotiation of previously acquired ownership interests and any resulting change in the estimated amount of consideration to be paid is adjusted in the reporting period through operating income or net interest expense, depending on the nature of the arrangement. See Note 9 for additional information on deferred acquisition consideration. Options to purchase . When acquiring less than 100% ownership, the Company may enter into agreements that give the Company an option to purchase, or require the Company to purchase, the incremental ownership interests under certain circumstances. Where the option to purchase the incremental ownership is within the Company’s control, the amounts are recorded as noncontrolling interests in the equity section of the Company’s balance sheet. Where the incremental purchase may be required of the Company, the amounts are recorded as redeemable noncontrolling interests in mezzanine equity at their acquisition date estimated redemption value and adjusted at each reporting period for changes to their estimated redemption value through additional paid-in capital (but not less than their initial redemption value), except for foreign currency translation adjustments. On occasion, the Company may initiate a renegotiation to acquire an incremental ownership interest and the amount of consideration paid may differ materially from the balance sheet amounts. See Note 12 for additional information on redeemable noncontrolling interests. Employment conditions. From time to time, specifically when the projected success of an acquisition is deemed to be dependent on retention of specific personnel, such acquisition may include deferred payments that are contingent upon employment terms as well as financial performance. The Company accounts for those payments through operating income as stock-based compensation over the required retention period. For the three and nine months ended September 30, 2016 and 2015 , stock-based compensation included $2,259 and $7,184 , respectively, and $1,548 and $6,462 , respectively, of expense relating to those payments. Distributions to minority shareholders. If minority shareholders have the right to receive distributions based on the profitability of an acquired entity, the amount is recorded as income attributable to noncontrolling interests. However, there are circumstances when the Company acquires a majority interest and the selling shareholders waive their right to receive distributions with respect to their retained interest for a period of time, typically not less than five years. Under this model, the right to receive such distributions typically begins concurrently with the purchase option period and, therefore, if such option is exercised at the first available date the Company may not record any minority interest over the entire period from the initial acquisition date through the acquisition date of the remaining interests. 2016 Acquisitions Effective July 1, 2016, the Company acquired 100% of the equity interests of Forsman & Bodenfors AB (“F&B”), an advertising agency based in Sweden, for an approximate purchase price range of $35,000 to $55,000 . The estimated aggregate purchase price at acquisition date of $49,837 , which is subject to adjustments, consisted of a closing payment of 1,900,000 MDC Class A subordinate voting shares with an acquisition date fair value of $34,219 , plus additional deferred acquisition payments with an estimated present value at acquisition date of $15,618 . The amount of additional payments will be calculated based on the financial results of the acquired business for 2015 and 2016 as well as for the value of the Company's shares from July 1, 2016 up to and including the close of business on November 2, 2016. At September 30, 2016 , the value of the closing payment consideration was $21,371 and the estimated present value of the additional deferred acquisition payments was $27,282 . The additional deferred acquisition payments are payable in 2017 at the Company's option through the payment of cash or the issuance of additional Class A subordinate voting shares. In the event the Company elects to settle the additional deferred payments through the issuance of Class A subordinate voting shares, such settlement amount will be subject to adjustment based on the value of the Company's shares determined at the close of business on the final trading day of the seller's applicable 90 day trading window. An allocation of excess purchase price consideration of this acquisition to the fair value of the net assets acquired resulted in identifiable intangibles of $36,698 , consisting primarily of customer lists, trade names and covenants not to compete, and goodwill of $24,778 , representing the value of the assembled workforce. The identified assets have a weighted average useful life of approximately 10.8 years and will be amortized in a manner represented by the pattern in which the economic benefits of the customer contracts/relationships are realized. In addition, the Company has recorded $2,275 as the present value of redeemable noncontrolling interests and $5,514 as the present value of noncontrolling interests both relating to the noncontrolling interest of F&B's subsidiaries. None of the intangibles and goodwill are tax deductible and the Company recorded a deferred tax liability of $8,074 related to the intangibles. F&B's results are included in the Reportable segment. The actual adjustments that the Company will ultimately make in finalizing the allocation of purchase price to fair value of the net assets acquired will depend on a number of factors. Included in the Company's consolidated statement of operations for the three and nine months ended September 30, 2016 was revenue of $15,527 and net loss of $12,305 related to the 2016 acquisition. The net loss was attributable to an increase in the deferred acquisition payment liability driven by the decrease in the estimated future market performance of the Company's stock price and the amortization of the intangibles identified in the allocation of the purchase price consideration. The following unaudited pro forma results of operations of the Company for the three and nine months ended September 30, 2016 and 2015 assume that the acquisition of F&B occurred on January 1, 2015. These unaudited pro forma results are not necessarily indicative of either the actual results of operations that would have been achieved had the acquisition of F&B taken place on January 1, 2015, or are they necessarily indicative of future results of operations. Three Months Ended September 30, Nine Months Ended September 30, 2016 2015 2016 2015 Revenues $ 349,254 $ 341,268 $ 1,036,055 $ 1,017,492 Net loss attributable to MDC Partners Inc. $ (21,295 ) $ (7,626 ) $ (43,874 ) $ (9,032 ) Loss per common share: Basic - net loss attributable to MDC Partners Inc. $ (0.41 ) $ (0.15 ) $ (0.84 ) $ (0.17 ) Diluted - net income loss attributable to MDC Partners Inc. $ (0.41 ) $ (0.15 ) $ (0.84 ) $ (0.17 ) Effective April 1, 2016, the Company acquired the remaining 40% ownership interests of Luntz Global Partners LLC. In 2016, the Company also entered into various non-material transactions in connection with other majority-owned entities. As a result of the foregoing, the Company made total cash closing payments of $1,089 , eliminated the contingent deferred acquisition payments of $4,052 and fixed deferred acquisition payments of $542 related to certain initial acquisition of the equity interests, reduced other assets by $428 , reduced accruals and other liabilities by $44 , reduced redeemable noncontrolling interest by $182 noncontrolling interests by $19,194 , and increased additional paid-in capital by $22,498 . Additional deferred payments with an estimated present value at acquisition date of $2,393 that are contingent upon service conditions have been excluded from deferred acquisition consideration and will be expensed as stock-based compensation over the required service period. 2015 Acquisitions Effective May 1, 2015, the Company acquired a majority of the equity interests of Y Media Labs LLC, such that following the transaction, the Company’s effective ownership was 60% . Effective October 31, 2015, the Company acquired substantially 100% of the assets of Unique Influence, LLC (and certain other affiliated entities). The aggregate purchase price of these acquisitions had an estimated present value at acquisition date of $55,279 and consisted of total closing cash payments of $23,000 and additional deferred acquisition payments that will be based on the future financial results of the underlying businesses from 2015 to 2020 with final payments due in 2022. These additional deferred payments have an estimated present value at acquisition date of $32,279 . An allocation of excess purchase price consideration of this acquisition to the fair value of the net assets acquired resulted in identifiable intangibles of $16,721 , consisting primarily of customer lists, trade names and covenants not to compete, and goodwill of $43,654 , representing the value of the assembled workforce. The identified assets have a weighted average useful life of approximately 6.3 years and will be amortized in a manner represented by the pattern in which the economic benefits of the customer contracts/relationships are realized. In addition, the Company has recorded $1,999 as the present value of redeemable noncontrolling interests. The Company expects intangibles and goodwill of $9,720 to be tax deductible. In 2015, the Company acquired incremental ownership interests of Sloane & Company LLC, Anomaly Partners LLC, Allison & Partners LLC, Relevent Partners LLC, Kenna Communications LP and 72andSunny Partners LLC. In addition, the Company also entered into various non-material transactions in connection with other majority owned entities. The aggregate purchase price for these 2015 acquisitions of incremental ownership interests has an estimated present value at transaction date of $200,822 and consisted of total closing cash payments of $37,467 and additional deferred acquisition payments that are both fixed and based on the future financial results of the underlying businesses from 2015 to 2021 with final payments due in 2022. These additional deferred payments have an estimated present value at acquisition date of $163,355 . The Company reduced redeemable noncontrolling interests by $149,335 and noncontrolling interests by $8,708 . The difference between the purchase price and the noncontrolling interests of $42,780 was recorded in additional paid-in capital. Noncontrolling Interests Changes in the Company’s ownership interests in our less than 100% owned subsidiaries during the three and nine months ended September 30, 2016 and 2015 were as follows: Net Loss Attributable to MDC Partners Inc. and Transfers (to) from the Noncontrolling Interests Three Months Ended September 30, Nine Months Ended September 30, 2016 2015 2016 2015 Net loss attributable to MDC Partners Inc. $ (33,530 ) $ (8,604 ) $ (55,650 ) $ (11,135 ) Transfers to (from) the noncontrolling interest: Increase (decrease) in MDC Partners Inc. paid-in capital for purchase of equity interests in excess of Redeemable Noncontrolling Interests and Noncontrolling Interests (520 ) (7,247 ) 22,498 (40,446 ) Net transfers to (from) noncontrolling interests $ (520 ) $ (7,247 ) $ 22,498 $ (40,446 ) Change from net loss attributable to MDC Partners Inc. and transfers to noncontrolling interests $ (34,050 ) $ (15,851 ) $ (33,152 ) $ (51,581 )

Accruals and Other Liabilities

Accruals and Other Liabilities	9 Months Ended
	Sep. 30, 2016
Accrued and Other Liabilities [Abstract]
Accruals and Other Liabilities	5. Accruals and Other Liabilities At September 30, 2016 and December 31, 2015 , accruals and other liabilities included accrued media of $144,864 and $187,540 , respectively; and included amounts due to noncontrolling interest holders, for their share of profits, which will be distributed within the next twelve months of $3,255 and $5,473 , respectively. Changes in amounts due to noncontrolling interest holders included in accrued and other liabilities for the year ended December 31, 2015 and nine months ended September 30, 2016 were as follows: Noncontrolling Balance, December 31, 2014 $ 6,014 Income attributable to noncontrolling interests 9,054 Distributions made (9,503 ) Other (1) (92 ) Balance, December 31, 2015 $ 5,473 Income attributable to noncontrolling interests 3,172 Distributions made (6,549 ) Other (1) 1,159 Balance, September 30, 2016 $ 3,255 (1) Other consists primarily of business acquisitions, sale of a business, step-up transactions, and cumulative translation adjustments.

Discontinued Operations

Discontinued Operations	9 Months Ended
	Sep. 30, 2016
Discontinued Operations and Disposal Groups [Abstract]
Discontinued Operations	6. Discontinued Operations Effective May 31, 2015, the Company completed the sale of Accent Marketing Services, L.L.C. for an aggregate selling price of $17,102 , net of transaction expenses. There were no discontinued operations for the three and nine months ended September 30, 2016 . Included in discontinued operations in the Company’s consolidated statements of operations for the three and nine months ended September 30, 2015 were the following: Three Months Ended Nine Months Ended 2015 2015 Revenue $ — $ 27,025 Operating income (loss) — (322 ) Other expense — (752 ) Gain (loss) on disposal (1,316 ) (5,207 ) Net income (loss) from discontinued operations attributable to MDC Partners Inc., net of taxes $ (1,316 ) $ (6,281 ) At September 30, 2016 and December 31, 2015 , the Company had no assets classified as held for sale.

Debt

Debt	9 Months Ended
	Sep. 30, 2016
Debt Disclosure [Abstract]
Debt	7. Debt The Company’s indebtedness was comprised as follows: September 30, December 31, 2015 Revolving credit agreement $ 70,497 $ — 6.50% Senior Notes due 2024 900,000 — 6.75% Senior Notes due 2020 — 735,000 Original issue premium — 5,838 Debt issuance costs (19,343 ) (12,625 ) 951,154 728,213 Obligations under capital leases 293 670 951,447 728,883 Less current portion: 260 470 $ 951,187 $ 728,413 6.50% Senior Notes On March 23, 2016, MDC entered into an indenture (the “Indenture”) among MDC, its existing and future restricted subsidiaries that guarantee, or are co-borrowers under or grant liens to secure, the Credit Agreement, as guarantors (the “Guarantors”) and The Bank of New York Mellon, as trustee, relating to the issuance by MDC of $900,000 aggregate principal amount of the 6.50% Notes. The 6.50% Notes were sold in a private placement in reliance on exceptions from registration under the the Securities Act of 1933. The 6.50% Notes bear interest at a rate of 6.50% per annum, accruing from March 23, 2016. Interest is payable semiannually in arrears on May 1 and November 1 of each year, beginning November 1, 2016. The 6.50% Notes mature on May 1, 2024 , unless earlier redeemed or repurchased. The Company received net proceeds from the offering of the 6.50% Notes equal to approximately $880,000 . The Company used the net proceeds to redeem all of its existing 6.75% Notes, together with accrued interest, related premiums, fees and expenses and recorded a charge for the loss on redemption of such notes of $33,298 , including write offs of unamortized original issue premium and debt issuance costs. Remaining proceeds were used for general corporate purposes, including funding of deferred acquisition consideration. The 6.50% Notes are guaranteed on a senior unsecured basis by all of MDC’s existing and future restricted subsidiaries that guarantee, or are co-borrowers under or grant liens to secure, the Credit Agreement. The 6.50% Notes are unsecured and unsubordinated obligations of MDC and rank (i) equally in right of payment with all of MDC’s or any Guarantor’s existing and future senior indebtedness, (ii) senior in right of payment to MDC’s or any Guarantor’s existing and future subordinated indebtedness, (iii) effectively subordinated to all of MDC’s or any Guarantor’s existing and future secured indebtedness to the extent of the collateral securing such indebtedness, including the Credit Agreement, and (iv) structurally subordinated to all existing and future liabilities of MDC’s subsidiaries that are not Guarantors. MDC may, at its option, redeem the 6.50% Notes in whole at any time or in part from time to time, on and after May 1, 2019 (i) at a redemption price of 104.875% of the principal amount thereof if redeemed during the twelve-month period beginning on May 1, 2019 , (ii) at a redemption price of 103.250% of the principal amount thereof if redeemed during the twelve-month period beginning on May 1, 2020 , (iii) at a redemption price of 101.625% of the principal amount thereof if redeemed during the twelve-month period beginning on May 1, 2021 , and (iv) at a redemption price of 100% of the principal amount thereof if redeemed on May 1, 2022 and thereafter. Prior to May 1, 2019 , MDC may, at its option, redeem some or all of the 6.50% Notes at a price equal to 100% of the principal amount of the 6.50% Notes plus a “make whole” premium and accrued and unpaid interest. MDC may also redeem, at its option, prior to May 1, 2019 , up to 35% of the 6.50% Notes with the proceeds from one or more equity offerings at a redemption price of 106.50% of the principal amount thereof. If MDC experiences certain kinds of changes of control (as defined in the Indenture), holders of the 6.50% Notes may require MDC to repurchase any 6.50% Notes held by them at a price equal to 101% of the principal amount of the 6.50% Notes plus accrued and unpaid interest. In addition, if MDC sells assets under certain circumstances, it must apply the proceeds from such sale and offer to repurchase the 6.50% Notes at a price equal to 100% of the principal amount plus accrued and unpaid interest. The Indenture includes covenants that, among other things, restrict MDC’s ability and the ability of its restricted subsidiaries (as defined in the Indenture) to incur or guarantee additional indebtedness; pay dividends on or redeem or repurchase the capital stock of MDC; make certain types of investments; create restrictions on the payment of dividends or other amounts from MDC’s restricted subsidiaries; sell assets; enter into transactions with affiliates; create liens; enter into sale and leaseback transactions; and consolidate or merge with or into, or sell substantially all of MDC’s assets to, another person. These covenants are subject to a number of important limitations and exceptions. The 6.50% Notes are also subject to customary events of default, including a cross-payment default and cross-acceleration provision. Redemption of 6.75% Senior Notes On March 23, 2016, the Company redeemed the 6.75% Notes in whole at a redemption price of 103.375% of the principal amount thereof with the proceeds from the issuance of the 6.50% Notes. Credit Agreement On March 20, 2013, MDC, Maxxcom Inc. (a subsidiary of MDC) and each of their subsidiaries party thereto entered into an amended and restated, $225 million senior secured revolving credit agreement due 2018 (the “Credit Agreement”) with Wells Fargo Capital Finance, LLC, as agent, and the lenders from time to time party thereto. Advances under the Credit Agreement are to be used for working capital and general corporate purposes, in each case pursuant to the terms of the Credit Agreement. Capitalized terms used in this section and not otherwise defined have the meanings set forth in the Credit Agreement. Effective October 23, 2014, MDC and its subsidiaries entered into an amendment to its Credit Agreement. The amendment: (i) expands the commitments under the facility by $100 million , from $225 million to $325 million ; (ii) extends the date by an additional eighteen months to September 30, 2019 ; (iii) reduces the base borrowing interest rate by 25 basis points (the applicable margin for borrowing is 1.00% in the case of Base Rate Loans and 1.75% in the case of LIBOR Rate Loans); and (iv) modifies certain covenants to provide the Company with increased flexibility to fund its continued growth and other general corporate purposes. Effective May 3, 2016, MDC and its subsidiaries entered into an additional amendment to its Credit Agreement. The amendment: (i) extends the date by an additional nineteen months to May 3, 2021 ; (ii) reduces the base borrowing interest rate by 25 basis points; (iii) provides the Company the ability to borrow in foreign currencies; and (iv) certain other modifications to provide additional flexibility in operating the Company’s business. Advances under the Credit Agreement bear interest as follows: (a)(i) Non-Prime Rate Loans bear interest at the Non-Prime Rate and (ii) all other Obligations bear interest at the Prime Rate, plus (b) an applicable margin. The applicable margin for borrowing is 1.50% in the case of Non-Prime Rate Loans and Prime Rate Loans that are European Advances, and 0.75% on all other Obligations. In addition to paying interest on outstanding principal under the Credit Agreement, MDC is required to pay an unused revolver fee of 0.25% to lenders under the Credit Agreement in respect of unused commitments thereunder. The Credit Agreement is guaranteed by substantially all of MDC’s present and future subsidiaries, other than immaterial subsidiaries and subject to customary exceptions. The Credit Agreement includes covenants that, among other things, restrict MDC’s ability and the ability of its subsidiaries to incur or guarantee additional indebtedness; pay dividends on or redeem or repurchase the capital stock of MDC; make certain types of investments; impose limitations on dividends or other amounts from MDC’s subsidiaries; incur certain liens, sell or otherwise dispose of certain assets; enter into transactions with affiliates; enter into sale and leaseback transactions; and consolidate or merge with or into, or sell substantially all of MDC’s assets to, another person. These covenants are subject to a number of important limitations and exceptions. The Credit Agreement also contains financial covenants, including a total leverage ratio, a senior leverage ratio, a fixed charge coverage ratio and a minimum earnings level (each as more fully described in the Credit Agreement). The Credit Agreement is also subject to customary events of default. The Company is currently in compliance with all of the terms and conditions of its Credit Agreement, and management believes, based on its current financial projections, that the Company will be in compliance with the covenants over the next twelve months. At September 30, 2016 , there were $70,497 borrowings under the Credit Agreement. At September 30, 2016 , the Company had issued $4,597 of undrawn outstanding letters of credit. At September 30, 2016 and December 31, 2015 , accounts payable included $56,026 and $73,558 of outstanding checks, respectively.

Fair Value Measurements

Fair Value Measurements	9 Months Ended
	Sep. 30, 2016
Fair Value Disclosures [Abstract]
Fair Value Measurements	9. Fair Value Measurements Authoritative guidance for fair value establishes a framework for measuring fair value. A fair value measurement assumes a transaction to sell an asset or transfer a liability occurs in the principal market for the asset or liability or, in the absence of a principal market, the most advantageous market for the asset or liability. In order to increase consistency and comparability in fair value measurements, the guidance establishes a hierarchy for observable and unobservable inputs used to measure fair value into three broad levels, which are described below: • Level 1 - Quoted prices (unadjusted) in active markets that are accessible at the measurement date for assets or liabilities. The fair value hierarchy gives the highest priority to Level 1 inputs. • Level 2 - Observable prices that are based on inputs not quoted on active markets, but corroborated by market data. • Level 3 - Unobservable inputs are used when little or no market data is available. The fair value hierarchy gives the lowest priority to Level 3 inputs. In determining fair value, the Company utilizes valuation techniques that maximize the use of observable inputs and minimize the use of unobservable inputs to the extent possible as well as considers counterparty credit risk in its assessment of fair value. Financial Liabilities Measured at Fair Value on a Recurring Basis The following tables present certain information for the financial liabilities that are disclosed at fair value on a recurring basis at September 30, 2016 and December 31, 2015 : Level 1 Level 1 September 30, 2016 December 31, 2015 Carrying Fair Value Carrying Fair Value Liabilities: 6.50% Senior Notes due 2024 $ 900,000 $ 832,500 $ — $ — 6.75% Senior Notes due 2020 — — 740,838 765,319 Long-term debt includes fixed rate debt. The fair value of this instrument is based on quoted market prices. The following table presents changes in deferred acquisition consideration: Fair Value Measurements Using Significant Unobservable Inputs September 30, December 31, 2016 2015 Beginning Balance of contingent payments $ 306,734 $ 172,227 Payments (1) (100,667 ) (77,301 ) Additions (2) 16,132 174,530 Redemption value adjustments (3) 21,131 41,636 Other (4) (6,412 ) — Foreign translation adjustment 1,389 (4,358 ) Ending Balance of contingent payments $ 238,307 $ 306,734 (1) For the nine months ended September 30, 2016 , payments include $10,458 of deferred acquisition consideration settled through the issuance of 691,559 MDC Class A subordinate voting shares in lieu of cash. (2) Additions are the initial estimated deferred acquisition payments of new acquisitions and step-up transactions completed within that fiscal period. (3) Redemption value adjustments are fair value changes from the Company’s initial estimates of deferred acquisition payments, including the accretion of present value and stock-based compensation charges relating to acquisition payments that are tied to continued employment. (4) Other is comprised of (i) $2,360 transfered to shares to be issued related to 100,000 MDC Class A subordinate voting shares to be issued contingent on specific thresholds of future earnings that management expects to be attained; and (ii) $4,052 of contingent payments eliminated through the acquisition of incremental ownership interests, see Note 4. In addition to the above amounts, there are fixed payments of $4,790 and $40,370 for total deferred acquisition consideration of $243,097 and $347,104 , which reconciles to the consolidated balance sheets at September 30, 2016 and December 31, 2015 , respectively. The Company includes the payments of all deferred acquisition consideration in financing activities in the Company’s consolidated statement of cash flows as the Company believes these payments to be seller-related financing activities, which is the predominant source of cash flows. The FASB recently issued new guidance regarding the classification of cash flows for contingent consideration that is effective January 1, 2018. See Note 13 for further information. Level 3 payments relate to payments made for deferred acquisition consideration. Level 3 grants relate to contingent purchase price obligations related to acquisitions and are recorded on the balance sheet at the acquisition date fair value. The estimated liability is determined in accordance with various contractual valuation formulas that may be dependent on future events, such as the growth rate of the earnings of the relevant subsidiary during the contractual period and, in some cases, the currency exchange rate as of the date of payment. Level 3 redemption value adjustments relate to the remeasurement and change in these various contractual valuation formulas as well as adjustments of present value. At September 30, 2016 and December 31, 2015 , the carrying amount of the Company’s financial instruments, including cash and cash equivalents, accounts receivable and accounts payable, approximated fair value because of their short-term maturity. The Company does not disclose the fair value for equity method investments or investments held at cost as it is not practical to estimate fair value since there is no readily available market data. Non-financial Assets and Liabilities that are Measured at Fair Value on a Nonrecurring Basis On a nonrecurring basis, the Company uses fair value measures when analyzing asset impairment. Long-lived assets and certain identifiable intangible assets are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. If it is determined such indicators are present and the review indicates that the assets will not be fully recoverable, based on undiscounted estimated cash flows over the remaining amortization periods, their carrying values are reduced to estimated fair value. Measurements based on undiscounted cash flows are considered to be Level 3 inputs. During the fourth quarter of each year, the Company evaluates goodwill and indefinite-lived intangibles for impairment at the reporting unit level. For each acquisition, the Company performed a detailed review to identify intangible assets and a valuation is performed for all such identified assets. The Company used several market participant measurements to determine estimated value. This approach includes consideration of similar and recent transactions, as well as utilizing discounted expected cash flow methodologies. The amounts allocated to assets acquired and liabilities assumed in the acquisitions were determined using Level 3 inputs. Fair value for property and equipment was based on other observable transactions for similar property and equipment. Accounts receivable represents the best estimate of balances that will ultimately be collected, which is based in part on allowance for doubtful accounts reserve criteria and an evaluation of the specific receivable balances.

Other Income (Expense)

Other Income (Expense)	9 Months Ended
	Sep. 30, 2016
Other Income and Expenses [Abstract]
Other Income (Expense)	10. Other Income (Expense) Three Months Ended September 30, Nine Months Ended September 30, 2016 2015 2016 2015 Other income (expense) $ 26 $ 4 $ (220 ) $ 482 Loss on sale of a business (1) (800 ) — (800 ) — Gain on sale of investments (2) 682 — 682 — Foreign currency transaction gain (loss) (5,916 ) (15,627 ) 9,868 (29,797 ) $ (6,008 ) $ (15,623 ) $ 9,530 $ (29,315 ) (1) Effective September 30, 2016, the Company sold all of its ownership interests in Bryan Mills to the noncontrolling shareholders and recognized a loss of $800 . (2) During the third quarter of 2016 , the Company sold one investment accounted for under the equity method and one investment accounted for under the cost method and recognized a gain of $682 .

Segment Information

Segment Information	9 Months Ended
	Sep. 30, 2016
Segment Reporting [Abstract]
Segment Information	11. Segment Information The Company determines an operating segment if a component (1) engages in business activities from which it earns revenues and incurs expenses, (2) has discrete financial information and that is (3) regularly reviewed by the Chief Operating Decision Maker (“CODM”) to make decisions regarding resource allocation for the segment and assess its performance. During June of 2016, the Company entered into a Separation and Release Agreement with its former Chief Operating Officer in connection with a limited restructuring of the Company’s corporate department. This change to the Company’s management structure was designed to provide the CODM greater visibility into the operating performance of individual Partner Firms and has resulted in a corresponding change in the level at which the CODM reviews of the operating results of such Partner Firms. As a result, in the third quarter of 2016, the Company reassessed its determination of operating segments and concluded that each Partner Firm represents an operating segment. The Company assessed the average long-term gross margins expected for each Partner Firm together with the qualitative characteristics set forth in ASC 280-10-50 and aggregated the Partner Firms that meet the aggregation criteria into one Reportable segment and combined and disclosed those Partner Firms that do not meet the aggregation criteria as an “all other” segment. The Company also reports the Corporate Group. • The Reportable segment is comprised of the Company's integrated advertising and media specialist agencies as well as public relations firms. These firms provide a comprehensive array of marketing and communications services for clients both domestically and globally. Firms within this segment include Allison + Partners, Anomaly, CPB, Doner, F&B, Hunter PR, KBS, MDC Media Partners, and 72andSunny, among others. These firms share similar characteristics related to the nature of their services as well as the type of clients and the methods used to provide their services. In addition, the class of customer is also common among the Partner Firms in this Reportable segment. This results in the firms having similar economics of their business. • All Other segment comprises the Company's specialist marketing offerings such as direct marketing, sales promotion, market research, strategic communications, database and customer relationship management, data analytics and insights, corporate identity, design and branding, and product and service innovation. Firms within this segment include Gale Partners, Kingsdale, Relevent, Team, Redscout and Y Media Labs. • The Corporate Group consists of corporate office expenses incurred in connection with the strategic resources provided to the Partner Firms, as well as certain other centrally managed expenses that are not fully allocated to the Reportable segments. These office and general expenses include (1) salaries and related expenses for corporate office employees including employees dedicated to supporting the Partner Firms, (2) occupancy expense relating to properties occupied by all corporate office employees, (3) other office and general expenses including professional fees for the financial statement audits and other public company costs, and (4) certain other professional fees managed by the corporate office. Additional expenses managed by the corporate office that are directly related to the Partner Firms are allocated to the Reportable segment. Prior year results have been recast to reflect the new segment reporting. Three Months Ended September 30, 2016 (thousands of United States dollars) Reportable Segment All Other Corporate Total Revenue $ 289,988 $ 59,266 $ — $ 349,254 Cost of services sold 193,677 41,982 — 235,659 Office and general expenses 65,407 11,204 6,692 83,303 Depreciation and amortization 10,070 983 359 11,412 Goodwill impairment — 29,631 — 29,631 Operating profit (loss) 20,834 (24,534 ) (7,051 ) (10,751 ) Other Income (Expense): Other expense, net (6,008 ) Interest expense and finance charges, net (16,322 ) Loss from continuing operations before income taxes and equity in earnings of non-consolidated affiliates (33,081 ) Income tax benefit (540 ) Loss from continuing operations before equity in earnings of non-consolidated affiliates (32,541 ) Equity in earnings of non-consolidated affiliates 70 Net loss (32,471 ) Net income attributable to the noncontrolling interests (962 ) (97 ) — (1,059 ) Net loss attributable to MDC Partners Inc. $ (33,530 ) Stock-based compensation $ 3,337 $ 1,286 $ 605 $ 5,228 Supplemental Segment Information: Capital expenditures $ 5,938 $ 337 $ — $ 6,275 Three Months Ended September 30, 2015 (thousands of United States dollars) Reportable Segment All Other Corporate Total Revenue $ 271,882 $ 56,533 $ — $ 328,415 Cost of services sold 173,944 38,981 — 212,925 Office and general expenses 50,425 8,897 19,464 78,786 Depreciation and amortization 8,095 4,654 337 13,086 Operating profit (loss) 39,418 4,001 (19,801 ) 23,618 Other Income (Expense): Other expense, net (15,623 ) Interest expense and finance charges, net (14,524 ) Loss from continuing operations before income taxes and equity in earnings of non-consolidated affiliates (6,529 ) Income tax benefit (1,191 ) Loss from continuing operations before equity in earnings of non-consolidated affiliates (5,338 ) Equity in earnings of non-consolidated affiliates 172 Loss from continuing operations (5,166 ) Loss from discontinued operations attributable to MDC Partners Inc., net of taxes (1,316 ) Net loss (6,482 ) Net income attributable to the noncontrolling interests (1,366 ) (756 ) — (2,122 ) Net loss attributable to MDC Partners Inc. $ (8,604 ) Stock-based compensation $ 1,857 $ 803 $ 606 $ 3,266 Supplemental Segment Information: Capital expenditures $ 7,650 $ 501 $ 10 $ 8,161 Nine Months Ended September 30, 2016 (thousands of United States dollars) Reportable Segment All Other Corporate Total Revenue $ 822,762 $ 172,581 $ — $ 995,343 Cost of services sold 558,854 117,086 — 675,940 Office and general expenses 171,310 30,814 31,716 233,840 Depreciation and amortization 24,462 8,340 1,266 34,068 Goodwill impairment — 29,631 — 29,631 Operating profit (loss) 68,136 (13,290 ) (32,982 ) 21,864 Other Income (Expense): Other income, net 9,530 Interest expense and finance charges, net (48,690 ) Loss on redemption of notes (33,298 ) Loss from continuing operations before income taxes and equity in earnings of non-consolidated affiliates (50,594 ) Income tax expense 1,893 Loss from continuing operations before equity in earnings of non-consolidated affiliates (52,487 ) Equity in earnings of non-consolidated affiliates 9 Net loss (52,478 ) Net income attributable to the noncontrolling interests (2,604 ) (568 ) — (3,172 ) Net loss attributable to MDC Partners Inc. $ (55,650 ) Stock-based compensation $ 11,067 $ 2,317 $ 2,059 $ 15,443 Supplemental Segment Information: Capital expenditures $ 17,440 $ 2,251 $ 32 $ 19,723 Goodwill and intangibles $ 751,511 $ 209,947 $ — $ 961,458 Total Assets $ 1,214,533 $ 292,081 $ 135,698 $ 1,642,312 Nine Months Ended September 30, 2015 (thousands of United States dollars) Reportable Segment All Other Corporate Total Revenue $ 804,399 $ 162,844 $ — $ 967,243 Cost of services sold 535,278 113,108 — 648,386 Office and general expenses 137,403 19,493 49,273 206,169 Depreciation and amortization 24,486 13,671 1,236 39,393 Operating profit (loss) 107,232 16,572 (50,509 ) 73,295 Other Income (Expense): Other expense, net (29,315 ) Interest expense and finance charges, net (42,684 ) Income from continuing operations before income taxes and equity in earnings of non-consolidated affiliates 1,296 Income tax benefit (566 ) Income from continuing operations before equity in earnings of non-consolidated affiliates 1,862 Equity in earnings of non-consolidated affiliates 627 Income from continuing operations 2,489 Loss from discontinued operations attributable to MDC Partners Inc., net of taxes (6,281 ) Net loss (3,792 ) Net income attributable to the noncontrolling interests (6,010 ) (1,333 ) — (7,343 ) Net loss attributable to MDC Partners Inc. $ (11,135 ) Stock-based compensation $ 7,763 $ 3,260 $ 2,002 $ 13,025 Supplemental Segment Information: Capital expenditures $ 16,084 $ 1,308 $ 273 $ 17,665 Goodwill and intangibles $ 695,839 $ 248,863 $ — $ 944,702 Total Assets $ 1,155,558 $ 324,242 $ 124,146 $ 1,603,946 A summary of the Company’s revenue by geographic area, based on the location in which the services originated, is set forth in the following table: United Canada Other Total Revenue Three Months Ended September 30, 2016 $ 274,506 $ 30,233 $ 44,515 $ 349,254 2015 $ 270,512 $ 29,559 $ 28,344 $ 328,415 Nine Months Ended September 30, 2016 $ 799,696 $ 92,253 $ 103,394 $ 995,343 2015 $ 793,904 $ 94,817 $ 78,522 $ 967,243

Commitments, Contingencies and

Commitments, Contingencies and Guarantees	9 Months Ended
	Sep. 30, 2016
Commitments and Contingencies Disclosure [Abstract]
Commitments, Contingencies and Guarantees	12. Commitments, Contingencies and Guarantees Deferred Acquisition Consideration. In addition to the consideration paid by the Company in respect of certain of its acquisitions at closing, additional consideration may be payable, or may be potentially payable based on the achievement of certain threshold levels of earnings. See Note 2 and Note 4. Options to purchase. Noncontrolling shareholders in certain subsidiaries have the right in certain circumstances to require the Company to acquire the remaining ownership interests held by them. The noncontrolling shareholders’ ability to exercise any such option right is subject to the satisfaction of certain conditions, including conditions requiring notice in advance of exercise and specific employment termination conditions. In addition, these rights cannot be exercised prior to specified staggered exercise dates. The exercise of these rights at their earliest contractual date would result in obligations of the Company to fund the related amounts during the remainder of 2016 to 2024 . It is not determinable, at this time, if or when the owners of these rights will exercise all or a portion of these rights. The amount payable by the Company in the event such rights are exercised is dependent on various valuation formulas and on future events, such as the average earnings of the relevant subsidiary through the date of exercise, the growth rate of the earnings of the relevant subsidiary during that period and, in some cases, the currency exchange rate at the date of payment. Management estimates, assuming that the subsidiaries owned by the Company at September 30, 2016 , perform over the relevant future periods at their trailing twelve-months earnings levels, that these rights, if all exercised, could require the Company, in future periods, to pay an aggregate amount of approximately $13,324 to the owners of such rights to acquire such ownership interests in the relevant subsidiaries. Of this amount, the Company is entitled, at its option, to fund approximately $126 by the issuance of share capital. In addition, the Company is obligated under similar contractual rights to pay an aggregate amount of approximately $43,790 only upon termination of such owner’s employment with the applicable subsidiary or death. The amount the Company would be required to pay to the noncontrolling interest holders should the Company acquire the remaining ownership interests is $3,060 less than the initial redemption value recorded in redeemable noncontrolling interests. Included in redeemable noncontrolling interests at September 30, 2016 was $60,174 of these options to purchase because they are not within the control of the Company. The ultimate amount payable relating to these transactions will vary because it is dependent on the future results of operations of the subject businesses and the timing of when these rights are exercised. Natural Disasters. Certain of the Company’s operations are located in regions of the United States which typically are subject to hurricanes. During the nine months ended September 30, 2016 and 2015 , these operations did not incur any costs related to damages resulting from hurricanes. Guarantees . Generally, the Company has indemnified the purchasers of certain assets in the event that a third party asserts a claim against the purchaser that relates to a liability retained by the Company. These types of indemnification guarantees typically extend for a number of years. Historically, the Company has not made any significant indemnification payments under such agreements and no amount has been accrued in the accompanying consolidated financial statements with respect to these indemnification guarantees. The Company continues to monitor the conditions that are subject to guarantees and indemnifications to identify whether it is probable that a loss has occurred, and would recognize any such losses under any guarantees or indemnifications in the period when those losses are probable and estimable. Legal Proceedings. The Company’s operating entities are involved in legal proceedings of various types. While any litigation contains an element of uncertainty, the Company has no reason to believe that the outcome of such proceedings or claims will have a material adverse effect on its financial condition or results of operations of the Company, except as set forth below in connection with the SEC investigation and the related class action litigation claims. SEC Investigation Update The Special Committee of the Board of Directors (the “Special Committee”) and management have continued to fully cooperate with the SEC in connection with its ongoing investigation of the Company. Mr. Nadal resigned from his position as CEO and as a Director of the Company’s Board of Directors, effective July 20, 2015, and agreed to repay to the Company specified expenses paid by the Company on his behalf and prior cash bonus awards. Specifically, as of December 31, 2015, Mr. Nadal repaid to the Company an aggregate amount equal to $11,285 in respect of perquisites and improper payments identified by the Special Committee. Separately, Mr. Nadal agreed to repay to the Company $10,582 in connection with amounts required to be repaid pursuant to cash bonus awards previously paid to Mr. Nadal, with such repayments to be made in five installments, with the last to be paid on December 31, 2017. Mr. Nadal repaid to the Company the first installment of $1,000 in September 2015 and the second installment of $1,500 in December 2015. The Company recorded a charge of approximately $5,338 in the third quarter of 2015 for the balance of prior cash bonus award amounts that will not be recovered. The SEC investigation remains ongoing. For the three and nine months ended September 30, 2016 , the Company has received insurance proceeds, net of professional expenses incurred of $2,463 and $725 , respectively, relating to the ongoing SEC investigation. For the three and nine months ended September 30, 2015 , the Company incurred $2,722 and $12,366 , respectively, of professional expenses. Class Action Litigation On July 31, 2015, North Collier Fire Control and Rescue District Firefighter Pension Plan (“North Collier”) filed a putative class action suit in the Southern District of New York, naming as defendants MDC, CFO David Doft, former CEO Miles Nadal, and former CAO Mike Sabatino. On December 11, 2015, North Collier and co-lead plaintiff Plymouth County Retirement Association filed an amended complaint, adding two additional defendants, Mitchell Gendel and Michael Kirby, a former member of MDC’s Board of Directors. The plaintiff alleges in the amended complaint violations of § 10(b), Rule 10b-5, and § 20 of the Securities Exchange Act of 1934, based on allegedly materially false and misleading statements in the Company’s SEC filings and other public statements regarding executive compensation, goodwill accounting, and the Company’s internal controls. The Company filed a motion to dismiss the amended complaint on February 9, 2016, the lead plaintiffs filed an opposition to that motion on April 8, 2016, and the Company filed a reply brief on May 9, 2016. By order granted on September 30, 2016, the U.S. District Court presiding over the case granted the Company’s motion to dismiss the plaintiffs’ amended complaint in its entirety with prejudice. On November 2, 2016, the lead plaintiffs filed a notice to appeal the U.S. District Court's ruling to the U.S. Court of Appeals for the Second Circuit. On August 7, 2015, Roberto Paniccia issued a Statement of Claim in the Ontario Superior Court of Justice in the City of Brantford, Ontario seeking to certify a class action suit naming the following as defendants: MDC, former CEO Miles S. Nadal, former CAO Michael C. Sabatino, CFO David Doft and BDO U.S.A. LLP. The Plaintiff alleges violations of section 138.1 of the Ontario Securities Act (and equivalent legislation in other Canadian provinces and territories) as well as common law misrepresentation based on allegedly materially false and misleading statements in the Company’s public statements, as well as omitting to disclose material facts with respect to the SEC investigation. The Company intends to continue to vigorously defend this suit. A case management judge has now been appointed but a date for an initial case conference has not yet been set. Commitments. At September 30, 2016 , the Company had issued $4,597 of undrawn outstanding letters of credit. In addition, the Company has commitments to fund investments in an aggregate amount of $891 .

New Accounting Pronouncements

New Accounting Pronouncements	9 Months Ended
	Sep. 30, 2016
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
New Accounting Pronouncements	13. New Accounting Pronouncements In August 2016, the FASB issued ASU 2016-15, Statement of Cash Flows. This new guidance is intended to reduce diversity in practice regarding the classification of certain transactions in the statement of cash flows. This guidance is effective January 1, 2018 and requires a retrospective transition method. Early adoption is permitted. The Company currently classifies all cash outflows for contingent consideration as a financing activity. Upon adoption the Company is required to classify only the original estimated liability as a financing activity and any changes as an operating activity. In March 2016, the FASB issued ASU 2016-09, which amended guidance on the accounting for employee share-based payments that requires all excess tax benefits and tax deficiencies to be recognized on the income statement instead of as additional paid-in capital, with prospective application required. The guidance also changes the classification of such tax benefits or tax deficiencies on the Consolidated Statement of Cash Flows from a financing activity to an operating activity, with prospective application required. Additionally, the ASU requires that the classification of cash paid by an employer when directly withholding shares for tax-withholding purposes should be classified as a financing activity on the Consolidated Statement of Cash Flows. This is consistent with the Company’s current classification. This amended guidance will be effective beginning January 1, 2017 and early adoption is permitted. The Company is currently assessing the impact of this guidance on its results of operations and related cash flows. In February 2016, the FASB issued ASU 2016-02, which amends the ASC and creates Topic 842, Leases. Topic 842 will require lessees to recognize lease assets and lease liabilities for those leases classified as operating leases under previous U.S. GAAP on the balance sheet. This guidance is effective for annual periods beginning after December 15, 2018 and early adoption is permitted. The Company is currently assessing the impact of this guidance on its consolidated financial position and results of operations. In January 2016, the FASB issued ASU 2016-01, Financial Instruments - Overall: Recognition and Measurement of Financial Assets and Liabilities , which will require equity investments, except equity method investments, to be measured at fair value and any changes in fair value will be recognized in results of operations. This guidance is effective for annual and interim periods beginning after December 15, 2017 and early application is not permitted. Additionally, this guidance provides for the recognition of the cumulative effect of retrospective application of the new standard in the period of initial application. The Company does not expect the application of this guidance to have a significant impact on its consolidated financial position or results of operations. In November 2015, the FASB issued ASU 2015-17, Income Taxes, which amends Topic 740 and requires all deferred income tax assets and liabilities to be presented as non-current on the balance sheet. This amended guidance is effective beginning January 1, 2017, and may be applied retrospectively or prospectively, with early adoption permitted. The Company does not expect the application of this guidance to have a significant impact on its consolidated financial position or results of operations. The FASB has issued amended guidance on revenue recognition, Topic 606, Revenue from Contracts with Customers, that supersedes Topic 605, Revenue Recognition, and requires an entity to recognize revenue when it transfers promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. In July 2015, the FASB affirmed its proposal to delay the effective date of the new revenue standard by one year to January 1, 2018, with early adoption to be permitted as of the original effective date of January 1, 2017. The Company is currently assessing the impact and choice of either the full or modified retrospective adoption method as well as impact the adoption of the amended guidance will have on its consolidated financial position and results of operations.

Goodwill and Intangible Assets

Goodwill and Intangible Assets	9 Months Ended
	Sep. 30, 2016
Goodwill [Abstract]
Goodwill Disclosure [Text Block]	8. Goodwill As of September 30, 2016 the goodwill by segment was as follows: Goodwill Reportable Segment All Other Total Balance, December 31, 2014 $ 660,792 $ 190,580 $ 851,372 Acquired goodwill 6,254 37,401 43,655 Acquisition purchase price adjustments (1,744 ) (684 ) (2,428 ) Foreign currency translation (10,263 ) (12,035 ) (22,298 ) Balance, December 31, 2015 $ 655,039 $ 215,262 $ 870,301 Acquired goodwill 24,778 — 24,778 Disposition — (764 ) (764 ) Impairment loss recognized — (29,631 ) (29,631 ) Foreign currency translation 351 3,448 3,799 Balance, September 30, 2016 $ 680,168 $ 188,315 $ 868,483 The results of the annual test on October 1, 2015, indicated fair value in excess of carrying amounts for each of the Company’s reporting units. The Company noted no significant events or conditions during the first and second quarter of 2016 that would have affected the conclusions from the annual assessment. During the third quarter of 2016, the Company changed its operating segments, as a result of the management structure change as discussed in Note 11, which resulted in a corresponding change to the Company’s reporting units. This coupled with a decline in operating performance of one of the Company’s experiential reporting units required the Company to perform interim goodwill impairment testing on this reporting unit. Additionally, another triggering event occurred relating to another non-material reporting unit. These two reporting units failed the first and second step of the goodwill impairment testing resulting in a goodwill impairment of $29,631 . Determining the fair value of a reporting unit involves the use of significant estimates and assumptions. The Company utilized both a market approach and income approach to estimate each reporting unit’s fair value. For the market approach the Company utilized both the guideline public company method and the precedent transaction method. The Company conducted a discounted cash flow analysis (income approach) to evaluate the fair value of the reporting unit to provide additional indication of fair value. The Company weighted the market and income approaches to arrive at an estimated fair value. The carrying value of these reporting units exceeded the estimated fair value, and therefore the Company conducted the second test of the goodwill impairment test. As a result of the second step there was a partial impairment of goodwill of $27,893 relating to the experiential reporting unit and $1,738 relating to a non-material reporting unit. During the third quarter of 2016, the Company wrote off goodwill of $764 related to the sale of its ownership interests in Bryan Mills to the noncontrolling shareholders. This write off is included in other income (expense).

Significant Accounting Polici21

Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2016
Accounting Policies [Abstract]
Goodwill and Intangible Assets, Goodwill, Policy [Policy Text Block]	Goodwill and Impairment of Goodwill. The Company reviews goodwill and other intangible assets with indefinite lives not subject to amortization for impairment annually as of October 1 st of each year or more frequently if indicators of potential impairment exist. For goodwill, impairment is assessed at the reporting unit level. During the third quarter of 2016 the Company changed its operating segments, as a result of the management structure change as discussed in Note 11, which resulted in a corresponding change to the Company’s reporting units. Each Partner Firm now represents an operating segment as well as a reporting unit for goodwill impairment testing. Due to triggering events during the third quarter of 2016 interim goodwill impairment testing was performed which resulted in an impairment of goodwill charge of approximately $29,631 . In addition, the Company sold all of its ownership interests in Bryan Mills Iradesso Corporation (“Bryan Mills”) to the noncontrolling shareholders, resulting in a write off of goodwill of $764 . See Note 8 for further information.
New Accounting Pronouncements and Changes in Accounting Principles [Text Block]	Accounting Change. On January 1, 2016, the Company retrospectively adopted the Financial Accounting Standards Board (the “FASB”) Accounting Standards Update (“ASU”) 2015-03, Interest - Imputation of Interest. This update requires that debt issuance costs related to a recognized debt liability be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability. As a result of the adoption of this update, the balance sheet at December 31, 2015 and September 30, 2015 was adjusted to reflect the reclassification of $12,625 and $13,254 , respectively, from other assets to long-term debt.
Subsidiary and Equity Investment Stock Transaction, Policy [Policy Text Block]	Subsidiary and Equity Investment Stock Transactions. Transactions involving the purchase, sale or issuance of stock of a subsidiary where control is maintained are recorded as a reduction in the redeemable noncontrolling interests or noncontrolling interests, as applicable. Any difference between the purchase price and noncontrolling interest are recorded to additional paid-in capital. In circumstances where the purchase of shares of an equity investment results in obtaining control, the existing carrying value of the investment is remeasured to the acquisition date fair value and any gain or loss is recognized in results of operations.
Earnings Per Share, Policy [Policy Text Block]	oss per Common Share . Basic loss per share is based upon the weighted average number of common shares outstanding during each period. “Share capital to be issued” as reflected in Shareholders’ Equity on the balance sheet are also included if there is no circumstance under which those shares would not be issued. Diluted income per share is based on the above, in addition, if dilutive, it also includes common share equivalents, which include outstanding options, stock appreciation rights, and unvested restricted stock units.
Foreign Currency Transactions and Translations Policy [Policy Text Block]	Foreign Currency Translation . The Company’s financial statements were prepared in accordance with the requirements of the Foreign Currency Translation topic of the FASB ASC. The functional currency of the Company is the Canadian dollar and it has decided to use U.S. dollars as its reporting currency for consolidated reporting purposes. Generally, the Company’s subsidiaries use their local currency as their functional currency. Accordingly, the currency impacts of the translation of the balance sheets of the Company’s non-U.S. dollar based subsidiaries to U.S. dollar statements are included as cumulative translation adjustments in accumulated other comprehensive income. Translation of intercompany debt, which is not intended to be repaid, is included in cumulative translation adjustments. Cumulative translation adjustments are not included in net earnings unless they are actually realized through a sale or upon complete or substantially complete liquidation of the Company’s net investment in the foreign operation. Translation of current intercompany balances are included in net earnings. The balance sheets of non-U.S. dollar based subsidiaries are translated at the period end rate. The income statements of non-U.S. dollar based subsidiaries are translated at average exchange rates for the period. Gains and losses arising from the Company’s foreign currency transactions are reflected in net earnings. Unrealized gains or losses arising on the translation of certain intercompany foreign currency transactions that are of a long-term nature (that is settlement is not planned or anticipated in the future) are included as cumulative translation adjustments in accumulated other comprehensive income.
Guarantees, Indemnifications and Warranties Policies [Policy Text Block]	Guarantees . Guarantees issued or modified by the Company to third parties after January 1, 2003 are generally recognized at the inception or modification of the guarantee as a liability for the obligations it has undertaken in issuing the guarantee, including its ongoing obligation to stand ready to perform over the term of the guarantee in the event that the specified triggering events or conditions occur. The initial measurement of that liability is the fair value of the guarantee. The recognition of a liability is required even if it is not probable that payments will be required under a guarantee. The Company’s liability associated with guarantees is not significant. (See Note 12.)
Premiums Receivable, Allowance for Doubtful Accounts, Estimation Methodology, Policy [Policy Text Block]	Allowance for Doubtful Accounts . Trade receivables are stated at invoiced amounts less allowances for doubtful accounts. The allowances represent estimated uncollectible receivables associated with potential customer defaults usually due to customers’ potential insolvency. The allowances include amounts for certain customers where a risk of default has been specifically identified. The assessment of the likelihood of customer defaults is based on various factors, including the length of time the receivables are past due, historical experience and existing economic conditions.
Expenditures Billable To Clients, Policy [Policy Text Block]	Expenditures Billable to Clients . Expenditures billable to clients consist principally of outside vendor costs incurred on behalf of clients when providing advertising, marketing and corporate communications services that have not yet been invoiced to clients. Such amounts are invoiced to clients at various times over the course of the production process.
Property, Plant and Equipment, Policy [Policy Text Block]	Fixed Assets . Fixed assets are stated at cost, net of accumulated depreciation. Computers, furniture and fixtures are depreciated on a straight-line basis over periods of three to seven years. Leasehold improvements are depreciated on a straight-line basis over the lesser of the term of the related lease or the estimated useful life of the asset. Repairs and maintenance costs are expensed as incurred.
Equity Method Investments, Policy [Policy Text Block]	Equity Method Investments. The equity method is used to account for investments in entities in which the Company has an ownership interest of less than 50% and has significant influence, or joint control by contractual arrangement, (i) over the operating and financial policies of the affiliate or (ii) has an ownership interest greater than 50% ; however, the substantive participating rights of the noncontrolling interest shareholders preclude the Company from exercising unilateral control over the operating and financial policies of the affiliate. The Company’s investments accounted for using the equity method include a 30% undivided interest in a real estate joint venture and various interests in investment funds. The Company’s management periodically evaluates these investments to determine if there has been a decline in value that is other than temporary. These investments are included in investments in non-consolidated affiliates.
Principles of Consolidation	Principles of Consolidation . The accompanying condensed consolidated financial statements include the accounts of MDC Partners Inc. and its domestic and international controlled subsidiaries that are not considered variable interest entities, and variable interest entities for which the Company is the primary beneficiary. Intercompany balances and transactions have been eliminated in consolidation.
Reclassification, Policy [Policy Text Block]	Reclassifications . Certain reclassifications have been made to the prior period financial statements to conform to the current period presentation.
Use of Estimates, Policy	Use of Estimates. The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions. These estimates and assumptions affect the reported amounts of assets and liabilities including goodwill, intangible assets, contingent deferred acquisition consideration, valuation allowances for receivables, deferred tax assets and the amounts of revenue and expenses reported during the period. These estimates are evaluated on an ongoing basis and are based on historical experience, current conditions and various other assumptions believed to be reasonable under the circumstances. Actual results could differ from these estimates.
Fair Value	Fair Value. The Company applies the fair value measurement guidance of the FASB Accounting Standards Codification (the “ASC”) Topic 820, Fair Value Measurements, for financial assets and liabilities that are required to be measured at fair value and for non-financial assets and liabilities that are not required to be measured at fair value on a recurring basis, including goodwill and other identifiable intangible assets. The measurement of fair value requires the use of techniques based on observable and unobservable inputs. Observable inputs reflect market data obtained from independent sources, while unobservable inputs reflect market assumptions. The inputs create the following fair value hierarchy: • Level 1 - Quoted 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 where inputs are observable or where significant value drivers are observable. • Level 3 - Instruments where significant value drivers are unobservable to third parties. When available, the Company uses quoted market prices to determine the fair value of its financial instruments and classifies such items in Level 1. In some cases, quoted market prices are used for similar instruments in active markets and the Company classifies such items in Level 2.
Concentration of Credit Risk	Concentration of Credit Risk. The Company provides marketing communications services to clients who operate in most industry sectors. Credit is granted to qualified clients in the ordinary course of business. Due to the diversified nature of the Company’s client base, the Company does not believe that it is exposed to a concentration of credit risk. No client accounted for more than 10% of the Company’s consolidated accounts receivable at September 30, 2016 and December 31, 2015 . No clients accounted for 10% of the Company’s revenue for the three and nine months ended September 30, 2016 or for the three and nine months ended September 30, 2015 .
Cash and Cash Equivalents	Cash and Cash Equivalents. The Company’s cash equivalents are primarily comprised of investments in overnight interest-bearing deposits, commercial paper and money market instruments and other short-term investments with original maturity dates of three months or less at the time of purchase. The Company has a concentration of credit risk in that there are cash deposits in excess of federally insured amounts.
Cash in Trust, Policy [Policy Text Block]	Cash in Trust. A subsidiary of the Company holds restricted cash in trust accounts related to funds received on behalf of clients. Such amounts are held in escrow under depositary service agreements and distributed at the direction of the clients. The funds are presented as a corresponding liability on the balance sheet
Cost Method Investments, Policy	Cost Method Investments. From time to time, the Company makes non-material cost based investments in start-up advertising technology companies and innovative consumer product companies where the Company does not exercise significant influence over the operating and financial policies of the investee. The total net cost basis of these investments, which is included in other assets on the balance sheet, at September 30, 2016 and December 31, 2015 was $10,607 and $11,763 , respectively. These investments are periodically evaluated to determine whether a significant event or change in circumstances has occurred that may impact the fair value of each investment other than temporary declines below book value. A variety of factors are considered when determining if a decline is other than temporary, including, among others, the financial condition and prospects of the investee, as well as the Company’s investment intent. In addition, the Company’s partner agencies may receive minority equity interests from start-up companies in lieu of fees.
Business Combinations	Business Combinations. Business combinations are accounted for using the acquisition method and accordingly, the assets acquired (including identified intangible assets), the liabilities assumed and any noncontrolling interest in the acquired business are recorded at their acquisition date fair values. The Company’s acquisition model typically provides for an initial payment at closing and for future additional contingent purchase price obligations. Contingent purchase price obligations are recorded as deferred acquisition consideration on the balance sheet at the acquisition date fair value and are remeasured at each reporting period. Changes in such estimated values are recorded in the results of operations. For further information see Note 4 and Note 9. For the three and nine months ended September 30, 2016 and 2015 , $11,152 and $17,180 of expense, respectively, and $4,928 of expense and $5,566 of income, respectively, related to changes in such estimated values was recorded in results of operations. The Company expenses acquisition related costs. For the three and nine months ended September 30, 2016 and 2015 , $806 and $2,266 , respectively, and $728 and $2,444 , respectively, of acquisition related costs were charged to operations. For each acquisition, the Company undertakes a detailed review to identify intangible assets and a valuation is performed for all such identified assets. The Company uses several market participant measurements to determine the estimated value. This approach includes consideration of similar and recent transactions, as well as utilizing discounted expected cash flow methodologies. Like most service businesses, a substantial portion of the intangible asset value that the Company acquires is the specialized know-how of the workforce, which is treated as part of goodwill and is not required to be valued separately. The majority of the value of the identifiable intangible assets acquired is derived from customer relationships, including the related customer contracts, as well as trade names. In executing the Company’s overall acquisition strategy, one of the primary drivers in identifying and executing a specific transaction is the existence of, or the ability to, expand the existing client relationships. The expected benefits of the Company’s acquisitions are typically shared across multiple agencies and regions.
Redeemable Noncontrolling Interest	Redeemable Noncontrolling Interests . Many of the Company’s acquisitions include contractual arrangements where the noncontrolling shareholders have an option to purchase, or may require the Company to purchase, such noncontrolling shareholders’ incremental ownership interests under certain circumstances and the Company has similar call options under the same contractual terms. The amount of consideration under these contractual arrangements is not a fixed amount, but rather is dependent upon various valuation formulas as described in Note 12. In the event that an incremental purchase may be required of the Company, the amounts are recorded as redeemable noncontrolling interests in mezzanine equity on the balance sheet at their acquisition date fair value and adjusted for changes to their estimated redemption value through additional paid-in capital (but not less than their initial redemption value), except for foreign currency translation adjustments. These adjustments will not impact the calculation of earnings (loss) per share if the redemption values are less than the estimated fair values. For the three and nine months ended September 30, 2016 and 2015 , there was no impact on the Company's earnings (loss) per share calculation. Changes in the estimated redemption amounts of the redeemable noncontrolling interests are adjusted at each reporting period with a corresponding adjustment to equity. These adjustments will not impact the calculation of earnings (loss) per share.
Variable Interest Entity	Variable Interest Entity . Effective March 28, 2012, the Company invested in Doner Partners LLC (“Doner”). The Company acquired a 30% voting interest and convertible preferred interests that allow the Company to increase ordinary voting ownership to 70% at the Company’s option. The Company has determined that (i) this entity is a variable interest entity, and (ii) the Company is the primary beneficiary because it receives a disproportionate share of profits and losses as compared to its ownership percentage. As such, Doner is consolidated for all periods subsequent to the date of investment. Doner is a full service integrated creative agency that is included as part of the Company’s portfolio in the Reportable segment. The Company’s Credit Agreement (see Note 7) is guaranteed and secured by all of Doner’s assets. Total assets and total liabilities of Doner included in the Company’s consolidated balance sheet at September 30, 2016 were $99,047 and $52,381 , respectively, and at December 31, 2015 were $122,558 and $86,047 , respectively.
Revenue Recognition	Revenue Recognition. The Company’s revenue recognition policies are established in accordance with the Revenue Recognition topics of the FASB ASC, and accordingly, revenue is recognized when all of the following criteria are satisfied: (i) persuasive evidence of an arrangement exists; (ii) the selling price is fixed or determinable; (iii) services have been performed or upon delivery of the products when ownership and risk of loss has transferred to the client; and (iv) collection of the resulting receivable is reasonably assured. The Company follows the Multiple-Element Arrangement topic of the FASB ASC, which addresses certain aspects of the accounting by a vendor for arrangements under which it will perform multiple revenue-generating activities and how to determine whether an arrangement involving multiple deliverables contains more than one unit of accounting. The Company follows the Principal Agent Consideration topic of the FASB ASC which addresses (i) whether revenue should be recorded at the gross amount billed because it has earned revenue from the sale of goods or services, or recorded at the net amount retained because it has earned a fee or commission, and (ii) that reimbursements received for out-of-pocket expenses incurred should be characterized in the income statement as revenue. Accordingly, the Company has included such reimbursed expenses in revenue. The Company earns revenue from agency arrangements in the form of retainer fees or commissions; from short-term project arrangements in the form of fixed fees or per diem fees for services; and from incentives or bonuses. Non-refundable retainer fees are generally recognized on a straight-line basis over the term of the specific customer arrangement. Commission revenue is earned and recognized upon the placement of advertisements in various media when the Company has no further performance obligations. Fixed fees for services are recognized upon completion of the earnings process and acceptance by the client. Per diem fees are recognized upon the performance of the Company’s services. In addition, for a limited number of certain service transactions, which require delivery of a number of service acts, the Company uses the proportional performance model, which generally results in revenue being recognized based on the straight-line method. Fees billed to clients in excess of fees recognized as revenue are classified as Advanced Billings on the Company’s balance sheet. A small portion of the Company’s contractual arrangements with customers includes performance incentive provisions, which allow the Company to earn additional revenue as a result of its performance relative to both quantitative and qualitative goals. The Company recognizes the incentive portion of revenue under these arrangements when specific quantitative goals are assured, or when the Company’s clients determine performance against qualitative goals has been achieved. In all circumstances, revenue is only recognized when collection is reasonably assured. The Company records revenue net of sales and other taxes due to be collected and remitted to governmental authorities.
Cost of Services Sold [Policy Text Block]	Cost of Services Sold . Cost of services sold do not include depreciation charges for fixed assets.
Interest Expense	Interest Expense . Interest expense primarily consists of the cost of borrowing on the Company’s previously outstanding 6.75% senior notes due 2020 (the “6.75% Notes”); the Company’s 6.50% senior unsecured notes due 2024 (the “6.50% Notes”); and the Company’s $325 million senior secured revolving credit agreement due 2021 (the “Credit Agreement”). The Company uses the effective interest method to amortize the deferred financing costs on the 6.75% Notes and the 6.50% Notes as well as the original issue premium on the 6.75% Notes. The Company also uses the straight-line method to amortize the deferred financing costs on the Credit Agreement. For the three and nine months ended September 30, 2016 and 2015 , interest expense included $30 and $181 , respectively, and $770 and $1,700 , respectively, relating to present value adjustments for fixed deferred acquisition consideration payments. The Company redeemed the 6.75% Notes with the net proceeds from the issuance of the 6.50% Notes. For further information see Note 7.
Income Tax	Income Taxes. The Company’s U.S. operating units are generally structured as limited liability companies, which are treated as partnerships for tax purposes. The Company is only taxed on its share of the profits, while noncontrolling holders are responsible for taxes on their share of the profits. The Company currently has a fully reserved valuation allowance on its deferred tax assets related to U.S. net operating losses. During the nine months ended September 30, 2016 and 2015 , the Company’s effective tax rate was lower than the statutory rate due primarily to losses in certain tax jurisdictions where a valuation allowance was deemed necessary.
Share-based Compensation	Stock-Based Compensation. Under the fair value method, compensation cost is measured at fair value at the date of grant and is expensed over the service period, in this case the award’s vesting period. When awards are exercised, share capital is credited by the sum of the consideration paid, together with the related portion previously credited to additional paid-in capital when compensation costs were charged against income or acquisition consideration. The Company uses its historical volatility derived over the expected term of the award to determine the volatility factor used in determining the fair value of the award. Stock-based awards that are settled in cash, or may be settled in cash at the option of employees, are recorded as liabilities. The measurement of the liability and compensation cost for these awards is based on the fair value of the award, and is recorded in operating income over the service period, in this case the award’s vesting period. Changes in the Company’s payment obligation prior to the settlement date of a stock-based award are recorded as compensation cost in operating income in the period of the change. The final payment amount for such awards is established on the date of the exercise of the award by the employee. Stock-based awards that are settled in cash or equity at the option of the Company are recorded at fair value on the date of grant and recorded as additional paid-in capital. The fair value measurement of the compensation cost for these awards is based on using the Black-Scholes option pricing-model and is recorded in operating income over the service period, in this case the award’s vesting period. It is the Company’s policy for issuing shares upon the exercise and/or vesting of an equity incentive award to calculate and verify the amount of shares to be issued, as well as the amount of proceeds to be collected (if any) and to deliver new shares to the exercising party. The Company has adopted the straight-line attribution method for determining the compensation cost to be recorded during each accounting period. However, awards based on performance conditions are recorded as compensation expense when the performance conditions are expected to be met. The Company treats benefits paid by shareholders or equity members to employees as a stock-based compensation charge with a corresponding credit to additional paid-in-capital. From time to time, certain acquisitions and step-up transactions include an element of compensation related payments. The Company accounts for those payments as stock-based compensation. During the nine months ended September 30, 2016 , the Company issued 296,000 shares of restricted stock and restricted stock units (collectively, “RSUs”) to its employees and directors. The RSUs have an aggregate grant date fair value of $4,454 and generally vest on the third anniversary of the date of grant. In addition, the Company awarded RSUs of which 523,321 awarded shares were outstanding as of September 30, 2016 . The vesting of these awards are contingent upon the Company meeting a cumulative three year earnings target and continued employment through the vesting date. Once the Company defines the earnings target, the grant date is established and the Company will record the compensation expense over the vesting period. A total of 1,404,081 Class A shares of RSUs, granted to employees as equity incentive awards but not yet vested, has been excluded in the Company’s calculation of Class A shares outstanding as of September 30, 2016 .

Significant Accounting Polici22

Significant Accounting Policies (Tables)	9 Months Ended
	Sep. 30, 2016
Accounting Policies [Abstract]
Redeemable Noncontrolling Interest	The following table presents changes in redeemable noncontrolling interests: Nine Months Ended September 30, 2016 Year Ended December 31, 2015 Beginning Balance $ 69,471 $ 194,951 Redemptions (890 ) (155,042 ) Additions (1) 2,274 7,703 Changes in redemption value (10,626 ) 22,809 Currency Translation Adjustments (55 ) (950 ) Ending Balance $ 60,174 $ 69,471 (1) Additions consist of transfers from noncontrolling interests related to step-up transactions and new acquisitions.

Loss Per Common Share (Tables)

Loss Per Common Share (Tables)	9 Months Ended
	Sep. 30, 2016
Earnings Per Share [Abstract]
Schedule of Calculation of Numerator and Denominator in Earnings Per Share	The following table sets forth the computation of basic and diluted loss per common share from continuing operations. Three Months Ended Nine Months Ended 2016 2015 2016 2015 Numerator Numerator for basic loss per common share - income (loss) from continuing operations $ (32,471 ) $ (5,166 ) $ (52,478 ) $ 2,489 Net income attributable to the noncontrolling interests (1,059 ) (2,122 ) (3,172 ) (7,343 ) Net loss from continuing operations attributable to MDC Partners Inc. common shareholders (33,530 ) (7,288 ) (55,650 ) (4,854 ) Effect of dilutive securities — — — — Numerator for diluted loss per common share - loss attributable to MDC Partners Inc. common shareholders from continuing operations $ (33,530 ) $ (7,288 ) $ (55,650 ) $ (4,854 ) Denominator Denominator for basic loss per common share - weighted average common shares 52,244,819 49,915,807 50,861,890 49,843,980 Effect of dilutive securities — — — — Denominator for diluted loss per common share - adjusted weighted shares and assumed conversions 52,244,819 49,915,807 50,861,890 49,843,980 Basic loss per common share from continuing operations $ (0.64 ) $ (0.15 ) $ (1.09 ) $ (0.10 ) Diluted loss per common share from continuing operations $ (0.64 ) $ (0.15 ) $ (1.09 ) $ (0.10 )

Acquisitions (Tables)

Acquisitions (Tables)	9 Months Ended
	Sep. 30, 2016
Business Combinations [Abstract]
Business Acquisition, Pro Forma Information [Table Text Block]	The following unaudited pro forma results of operations of the Company for the three and nine months ended September 30, 2016 and 2015 assume that the acquisition of F&B occurred on January 1, 2015. These unaudited pro forma results are not necessarily indicative of either the actual results of operations that would have been achieved had the acquisition of F&B taken place on January 1, 2015, or are they necessarily indicative of future results of operations. Three Months Ended September 30, Nine Months Ended September 30, 2016 2015 2016 2015 Revenues $ 349,254 $ 341,268 $ 1,036,055 $ 1,017,492 Net loss attributable to MDC Partners Inc. $ (21,295 ) $ (7,626 ) $ (43,874 ) $ (9,032 ) Loss per common share: Basic - net loss attributable to MDC Partners Inc. $ (0.41 ) $ (0.15 ) $ (0.84 ) $ (0.17 ) Diluted - net income loss attributable to MDC Partners Inc. $ (0.41 ) $ (0.15 ) $ (0.84 ) $ (0.17 )
Schedule of Net Income (Loss) Attributable to Parent and Transfers to and from Noncontrolling Interest	Changes in the Company’s ownership interests in our less than 100% owned subsidiaries during the three and nine months ended September 30, 2016 and 2015 were as follows: Net Loss Attributable to MDC Partners Inc. and Transfers (to) from the Noncontrolling Interests Three Months Ended September 30, Nine Months Ended September 30, 2016 2015 2016 2015 Net loss attributable to MDC Partners Inc. $ (33,530 ) $ (8,604 ) $ (55,650 ) $ (11,135 ) Transfers to (from) the noncontrolling interest: Increase (decrease) in MDC Partners Inc. paid-in capital for purchase of equity interests in excess of Redeemable Noncontrolling Interests and Noncontrolling Interests (520 ) (7,247 ) 22,498 (40,446 ) Net transfers to (from) noncontrolling interests $ (520 ) $ (7,247 ) $ 22,498 $ (40,446 ) Change from net loss attributable to MDC Partners Inc. and transfers to noncontrolling interests $ (34,050 ) $ (15,851 ) $ (33,152 ) $ (51,581 )

Accruals and Other Liabilities

Accruals and Other Liabilities (Tables)	9 Months Ended
	Sep. 30, 2016
Accrued and Other Liabilities [Abstract]
Accrued and Other Liabilities Disclosure	5. Accruals and Other Liabilities At September 30, 2016 and December 31, 2015 , accruals and other liabilities included accrued media of $144,864 and $187,540 , respectively; and included amounts due to noncontrolling interest holders, for their share of profits, which will be distributed within the next twelve months of $3,255 and $5,473 , respectively. Changes in amounts due to noncontrolling interest holders included in accrued and other liabilities for the year ended December 31, 2015 and nine months ended September 30, 2016 were as follows: Noncontrolling Balance, December 31, 2014 $ 6,014 Income attributable to noncontrolling interests 9,054 Distributions made (9,503 ) Other (1) (92 ) Balance, December 31, 2015 $ 5,473 Income attributable to noncontrolling interests 3,172 Distributions made (6,549 ) Other (1) 1,159 Balance, September 30, 2016 $ 3,255 (1) Other consists primarily of business acquisitions, sale of a business, step-up transactions, and cumulative translation adjustments.

Discontinued Operations (Tables

Discontinued Operations (Tables)	9 Months Ended
	Sep. 30, 2016
Discontinued Operations and Disposal Groups [Abstract]
Schedule of Disposal Groups, Including Discontinued Operations, Income Statement, Balance Sheet and Additional Disclosures	There were no discontinued operations for the three and nine months ended September 30, 2016 . Included in discontinued operations in the Company’s consolidated statements of operations for the three and nine months ended September 30, 2015 were the following: Three Months Ended Nine Months Ended 2015 2015 Revenue $ — $ 27,025 Operating income (loss) — (322 ) Other expense — (752 ) Gain (loss) on disposal (1,316 ) (5,207 ) Net income (loss) from discontinued operations attributable to MDC Partners Inc., net of taxes $ (1,316 ) $ (6,281 )

Debt (Tables)

Debt (Tables)	9 Months Ended
	Sep. 30, 2016
Debt Disclosure [Abstract]
Schedule of Debt	The Company’s indebtedness was comprised as follows: September 30, December 31, 2015 Revolving credit agreement $ 70,497 $ — 6.50% Senior Notes due 2024 900,000 — 6.75% Senior Notes due 2020 — 735,000 Original issue premium — 5,838 Debt issuance costs (19,343 ) (12,625 ) 951,154 728,213 Obligations under capital leases 293 670 951,447 728,883 Less current portion: 260 470 $ 951,187 $ 728,413

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	9 Months Ended
	Sep. 30, 2016
Fair Value, Inputs, Level 1
Fair Value, Liabilities Measured on Recurring and Nonrecurring Basis	The following tables present certain information for the financial liabilities that are disclosed at fair value on a recurring basis at September 30, 2016 and December 31, 2015 : Level 1 Level 1 September 30, 2016 December 31, 2015 Carrying Fair Value Carrying Fair Value Liabilities: 6.50% Senior Notes due 2024 $ 900,000 $ 832,500 $ — $ — 6.75% Senior Notes due 2020 — — 740,838 765,319
Fair Value, Inputs, Level 3
Fair Value, Liabilities Measured on Recurring and Nonrecurring Basis	The following table presents changes in deferred acquisition consideration: Fair Value Measurements Using Significant Unobservable Inputs September 30, December 31, 2016 2015 Beginning Balance of contingent payments $ 306,734 $ 172,227 Payments (1) (100,667 ) (77,301 ) Additions (2) 16,132 174,530 Redemption value adjustments (3) 21,131 41,636 Other (4) (6,412 ) — Foreign translation adjustment 1,389 (4,358 ) Ending Balance of contingent payments $ 238,307 $ 306,734 (1) For the nine months ended September 30, 2016 , payments include $10,458 of deferred acquisition consideration settled through the issuance of 691,559 MDC Class A subordinate voting shares in lieu of cash. (2) Additions are the initial estimated deferred acquisition payments of new acquisitions and step-up transactions completed within that fiscal period. (3) Redemption value adjustments are fair value changes from the Company’s initial estimates of deferred acquisition payments, including the accretion of present value and stock-based compensation charges relating to acquisition payments that are tied to continued employment. (4) Other is comprised of (i) $2,360 transfered to shares to be issued related to 100,000 MDC Class A subordinate voting shares to be issued contingent on specific thresholds of future earnings that management expects to be attained; and (ii) $4,052 of contingent payments eliminated through the acquisition of incremental ownership interests, see Note 4.

Other Income (Expense) (Tables)

Other Income (Expense) (Tables)	9 Months Ended
	Sep. 30, 2016
Other Income and Expenses [Abstract]
Schedule of Other Nonoperating Income (Expense)	Other Income (Expense) Three Months Ended September 30, Nine Months Ended September 30, 2016 2015 2016 2015 Other income (expense) $ 26 $ 4 $ (220 ) $ 482 Loss on sale of a business (1) (800 ) — (800 ) — Gain on sale of investments (2) 682 — 682 — Foreign currency transaction gain (loss) (5,916 ) (15,627 ) 9,868 (29,797 ) $ (6,008 ) $ (15,623 ) $ 9,530 $ (29,315 )

Segment Information (Tables)

Segment Information (Tables)	9 Months Ended
	Sep. 30, 2016
Segment Reporting [Abstract]
Schedule of Segment Reporting Information, by Segment
Schedule of Revenue from External Customers Attributed to Foreign Countries by Geographic Area	A summary of the Company’s revenue by geographic area, based on the location in which the services originated, is set forth in the following table: United Canada Other Total Revenue Three Months Ended September 30, 2016 $ 274,506 $ 30,233 $ 44,515 $ 349,254 2015 $ 270,512 $ 29,559 $ 28,344 $ 328,415 Nine Months Ended September 30, 2016 $ 799,696 $ 92,253 $ 103,394 $ 995,343 2015 $ 793,904 $ 94,817 $ 78,522 $ 967,243

Significant Accounting Polici31

Significant Accounting Policies (Details) - USD ($)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Significant Accounting Policies [Line Items]
Option to purchase noncontrolling interest impairment charge	$ 0	$ 0	$ 0	$ 0
Beginning Balance			69,471,000
Granted			8,819,000
Ending Balance	60,174,000		60,174,000		$ 69,471,000
Redeemable Noncontrolling Interest [Member]
Significant Accounting Policies [Line Items]
Beginning Balance			69,471,000	$ 194,951,000	194,951,000
Redemptions			(890,000)		(155,042,000)
Granted			2,274,000		7,703,000
Changes in redemption value			(10,626,000)		22,809,000
Currency Translation Adjustments			(55,000)		(950,000)
Ending Balance	$ 60,174,000		$ 60,174,000		$ 69,471,000

Significant Accounting Polici32

Significant Accounting Policies (Details Textual)	May 01, 2024	May 03, 2016	Mar. 23, 2016	Oct. 23, 2014USD ($)	Mar. 28, 2012	Sep. 30, 2016USD ($)Clientsshares	Sep. 30, 2015USD ($)Clients	Sep. 30, 2016USD ($)Clientsshares	Sep. 30, 2015USD ($)Clients	Dec. 31, 2015USD ($)Clients	Dec. 31, 2014USD ($)	Mar. 20, 2013
Significant Accounting Policies [Line Items]
Redeemable Noncontrolling Interest, Equity, Fair Value						$ 60,174,000		$ 60,174,000		$ 69,471,000
Noncontrolling Interest, Increase from Business Combination								8,819,000
Debt Issuance Costs, Net						$ (19,343,000)	$ (13,254,000)	$ (19,343,000)	$ (13,254,000)	$ (12,625,000)
Clients exceeding consolidated accounts receivable percentage | Clients						0		0		0
Interest Rate Percentage On Senior Notes						6.75%		6.75%
Put option noncontrolling interest impairment charge						$ 0	$ 0	$ 0	$ 0
Cost Method Investments						$ 10,607,000		$ 10,607,000		$ 11,763,000
Consolidated Accounts Receivable Percentage						10.00%		10.00%		10.00%
Clients exceeding consolidated largest client revenue | Clients						0	0	0	0
Consolidated Largest Client Revenue						10.00%	10.00%	10.00%	10.00%
Business Combination, Acquisition Related Costs						$ 806,000	$ 728,000	$ 2,266,000	$ 2,444,000
Assets						1,642,312,000	1,603,946,000	1,642,312,000	1,603,946,000	$ 1,577,625,000
Liabilities						2,094,019,000		2,094,019,000		1,995,227,000
Adjustment to deferred acquisition consideration included in interest expense						30,000	770,000	181,000	1,700,000
Goodwill, Impairment Loss						29,631,000	0	29,631,000	0
Goodwill, Written off Related to Sale of Business Unit						$ (764,000)		$ 764,000
Common Class A
Significant Accounting Policies [Line Items]
Aggregate Non-Vested, Shares, Restricted Stock Issued, Gross | shares						1,404,081		1,404,081
Doner [Member]
Significant Accounting Policies [Line Items]
Variable Interest Entity, Qualitative or Quantitative Information, Ownership Percentage					30.00%
Assets						$ 99,047,000		$ 99,047,000		122,558,000
Liabilities						$ 52,381,000		$ 52,381,000		86,047,000
Aggregate 2015 Step Up Transactions [Member]
Significant Accounting Policies [Line Items]
Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests										$ 149,335
Aggregate 2012 Acquisitions [Member] | Doner [Member]
Significant Accounting Policies [Line Items]
Ownership Interest Percentage Increase On Exercise Of Option					70.00%
Minimum [Member]
Significant Accounting Policies [Line Items]
Property, Plant and Equipment, Useful Life								3 years
Maximum [Member]
Significant Accounting Policies [Line Items]
Property, Plant and Equipment, Useful Life								7 years
Equity Method Investment, Ownership Percentage						50.00%		50.00%
Real Estate Joint Venture [Member]
Significant Accounting Policies [Line Items]
Equity Method Investment, Ownership Percentage										30.00%
Wells Fargo Capital Finance, LLC
Significant Accounting Policies [Line Items]
Debt Instrument, Maturity Date		May 3, 2021		Sep. 30, 2019
Line of Credit Facility, Maximum Borrowing Capacity				$ 325,000,000
Contingent payment [Domain]
Significant Accounting Policies [Line Items]
Business Combination, Contingent Consideration Arrangements, Change in Amount of Contingent Consideration, Liability						$ 11,152,000	$ 4,928,000	$ 17,180,000	$ (5,566,000)
Notes due 2020 [Member]
Significant Accounting Policies [Line Items]
Debt Instrument, Interest Rate, Stated Percentage						6.75%		6.75%
Six Point Seven Five Percentage Notes [Member]
Significant Accounting Policies [Line Items]
Debt Instrument, Interest Rate, Stated Percentage												6.75%
Six Point Seven Five Percentage Notes [Member] | Wells Fargo Capital Finance, LLC
Significant Accounting Policies [Line Items]
Debt Instrument, Maturity Date			Apr. 1, 2020
Notes due 2024 [Domain]
Significant Accounting Policies [Line Items]
Debt Instrument, Interest Rate, Stated Percentage						6.50%		6.50%
Six Point Five Zero Percentage Notes [Domain]
Significant Accounting Policies [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			6.50%			6.50%		6.50%
Restricted Stock Units (RSUs) [Member] | Common Class A
Significant Accounting Policies [Line Items]
Stock Issued During Period, Shares, Restricted Stock Award, Gross | shares								296,000
Restricted stock grant date fair value								$ 4,454,000
Stock Issued During Period, Shares, Restricted Stock Award, Gross | shares								523,321
Scenario, Forecast [Member] | Six Point Five Zero Percentage Notes [Domain]
Significant Accounting Policies [Line Items]
Debt Instrument, Maturity Date	May 1, 2024
Scenario, Forecast [Member] | Six Point Five Zero Percentage Notes [Domain] | Wells Fargo Capital Finance, LLC
Significant Accounting Policies [Line Items]
Debt Instrument, Maturity Date	May 1, 2024
Noncontrolling Interest Equity [Domain] | Aggregate 2016 Step Up Transactions [Member]
Significant Accounting Policies [Line Items]
Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests								$ 19,194
Redeemable Noncontrolling Interest [Member]
Significant Accounting Policies [Line Items]
Redeemable Noncontrolling Interest, Equity, Fair Value						$ 60,174,000		60,174,000		$ 69,471,000	$ 194,951,000
Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests								890,000		155,042,000
Noncontrolling Interest, Increase from Business Combination								2,274,000		7,703,000
Changes in redemption value								(10,626,000)		22,809,000
Redeemable Noncontrolling Interest Currency Adjustments								$ (55,000)		$ (950,000)

Loss Per Common Share (Details)

Loss Per Common Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Earnings Per Share [Abstract]
Income from continuing operations	$ (32,471)	$ (5,166)	$ (52,478)	$ 2,489
Numerator
Net income attributable to the noncontrolling interests	(1,059)	(2,122)	(3,172)	(7,343)	$ (9,054)
Income (Loss) from Continuing Operations Attributable to Parent	(33,530)	(7,288)	(55,650)	(4,854)
Effect of dilutive securities	0	0	0	0
Income (Loss) from Continuing Operations Attributable to Parent, Diluted	$ (33,530)	$ (7,288)	$ (55,650)	$ (4,854)
Denominator
Denominator for basic loss per common share - weighted average common shares	52,244,819	49,915,807	50,861,890	49,843,980
Effect of dilutive securities	0	0	0	0
Denominator for diluted loss per common share - adjusted weighted shares and assumed conversions	52,244,819	49,915,807	50,861,890	49,843,980
Income (loss) from continuing operations attributable to MDC Partners Inc. common shareholders (usd per share)	$ (0.64)	$ (0.15)	$ (1.09)	$ (0.10)
Income (loss) from continuing operations attributable to MDC Partners Inc. common shareholders (usd per share)	$ (0.64)	$ (0.15)	$ (1.09)	$ (0.10)

Loss Per Common Share (Details

Loss Per Common Share (Details Textual) - shares	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	918,260		918,260
Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements		942,574		942,574
Restricted Stock Units (RSUs)
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	880,760		880,760
Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements		867,574		867,574
Contingent Restricted Stock Units (RSUs) [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	523,321		523,321

Acquisitions (Details)

Acquisitions (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Net loss attributable to MDC Partners Inc.	$ (33,530)	$ (8,604)	$ (55,650)	$ (11,135)
Transfers to (from) the noncontrolling interest:
Net transfers to (from) noncontrolling interests	(520)	(7,247)	22,498	(40,446)
Change from net loss attributable to MDC Partners Inc. and transfers to noncontrolling interests	(34,050)	(15,851)	(33,152)	(51,581)
Additional Paid-in Capital [Member]
Net loss attributable to MDC Partners Inc.
Parent [Member]
Net loss attributable to MDC Partners Inc.			(55,650)
Increase Decrease in Redeemable and Non Redeemable Non Controlling Interest from Step up Transactions	$ (520)	$ (7,247)	$ 22,498	$ (40,446)

Acquisitions (Details Textual)

Acquisitions (Details Textual) - USD ($)	Sep. 30, 2016	Jul. 01, 2016	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015	Apr. 01, 2016	Oct. 01, 2015	May 01, 2015
Business Acquisition [Line Items]
Business Acquisition, Pro Forma Revenue			$ 349,254,000	$ 341,268,000	$ 1,036,055,000	$ 1,017,492,000
Adjustments to deferred acquisition consideration included in share-based compensation			2,259	1,548	7,184	6,462
Goodwill, Acquired During Period					24,778,000		$ 43,655,000
Business Acquisition, Pro Forma Net Income (Loss)			(33,530,000)	(8,604,000)	(55,650,000)	(11,135,000)
Redeemable Noncontrolling Interest, Equity, Fair Value	$ 60,174,000		$ 60,174,000		$ 60,174,000		69,471,000
Noncontrolling Interest, Ownership Percentage by Parent	100.00%		100.00%		100.00%
Business Combination, Contingent Consideration, Liability	$ 243,097,000		$ 243,097,000		$ 243,097,000		347,104,000
Business Acquisition, Pro Forma Net Income (Loss)			$ (21,295,000)	$ (7,626,000)	$ (43,874,000)	$ (9,032,000)
Basic Earnings Per Share, Pro Forma			$ (410)	$ (150)	$ (840)	$ (170)
Diluted Earnings Per Share Pro Forma			$ (410)	$ (150)	$ (840)	$ (170)
Forsman & Bodenfors AB [Domain]
Business Acquisition [Line Items]
Business Acquisition, Pro Forma Revenue			$ 15,527
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles		$ 36,698
Goodwill, Acquired During Period		$ 24,778
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life		10 years 9 months
Business Combination, Acquisition of Less than 100 Percent, Redeemable Noncontrolling Interest, Fair Value		$ 2,275
Business Combination, Acquisition of Less than 100 Percent, Noncontrolling Interest, Fair Value		5,514
Business Acquisition, Goodwill, Expected Tax Deductible Amount		0
Deferred Taxes, Business Combination, Valuation Allowance, Available to Reduce Intangible Assets		$ 8,074
Business Acquisition, Pro Forma Revenue					$ 15,527
Business Acquisition, Pro Forma Net Income (Loss)					12,305
Business Acquisition, Percentage of Voting Interests Acquired		100.00%
Business Combination, Consideration Transferred		$ 49,837
Business Combination, Contingent Consideration, Liability	27,282	15,618	27,282		27,282
Business Acquisition, Pro Forma Net Income (Loss)			12,305
Luntz Global Partners L L C
Business Acquisition [Line Items]
Business Acquisition, Percentage of Voting Interests Acquired								40.00%
Aggregate 2016 Step Up Transactions [Member]
Business Acquisition [Line Items]
Business Acquisition, Cost of Acquired Entity, Cash Paid					1,089
Business Combination, Acquisition of Less than 100 Percent, Redeemable Noncontrolling Interest, Fair Value					182
Business Combinations, Assets Relinquished by Acquirer					428
Business Combinations, Liabilities Relinquished Previously due to Acquiree					44
Aggregate 2015 Acquisitions [Member]
Business Acquisition [Line Items]
Business Acquisition, Cost of Acquired Entity, Cash Paid							23,000
Business Combination, Consideration Transferred, Liabilities Incurred							32,279
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles							16,721
Goodwill, Acquired During Period							$ 43,654
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life							6 years 4 months
Business Acquisition, Goodwill, Expected Tax Deductible Amount							$ 9,720
Business Combination, Consideration Transferred							55,279
Aggregate 2015 Acquisitions [Member] | Y Media Labs, LLC [Member]
Business Acquisition [Line Items]
Business Combination, Acquisition of Less than 100 Percent, Noncontrolling Interest, Fair Value							1,999
Business Acquisition, Percentage of Voting Interests Acquired										60.00%
Aggregate 2015 Acquisitions [Member] | Unique Influence, LLC [Domain]
Business Acquisition [Line Items]
Business Acquisition, Percentage of Voting Interests Acquired									100.00%
Aggregate 2015 Step Up Transactions [Member]
Business Acquisition [Line Items]
Business Acquisition, Cost of Acquired Entity, Cash Paid							37,467
Business Combination, Consideration Transferred, Liabilities Incurred							163,355
Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests							149,335
Business Combination, Consideration Transferred							200,822
Minimum [Member] | Forsman & Bodenfors AB [Domain]
Business Acquisition [Line Items]
Business Combination, Consideration Transferred		35,000
Maximum [Member] | Forsman & Bodenfors AB [Domain]
Business Acquisition [Line Items]
Business Combination, Consideration Transferred		$ 55,000
Noncontrolling Interest [Member]
Business Acquisition [Line Items]
Business Acquisition, Pro Forma Net Income (Loss)					0
Noncontrolling Interest [Member] | Aggregate 2015 Step Up Transactions [Member]
Business Acquisition [Line Items]
Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests							8,708
Additional Paid-in Capital [Member]
Business Acquisition [Line Items]
Business Acquisition, Pro Forma Net Income (Loss)
Additional Paid-in Capital [Member] | Aggregate 2016 Step Up Transactions [Member]
Business Acquisition [Line Items]
Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests					22,498
Additional Paid-in Capital [Member] | Aggregate 2015 Step Up Transactions [Member]
Business Acquisition [Line Items]
Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests							42,780
Contingent payment [Domain]
Business Acquisition [Line Items]
Business Combination, Contingent Consideration Arrangements, Change in Amount of Contingent Consideration, Liability			11,152,000	$ 4,928,000	17,180,000	$ (5,566,000)
Contingent payment [Domain] | Aggregate 2016 Step Up Transactions [Member]
Business Acquisition [Line Items]
Deferred Stock-based Compensation, Discounted					2,393
Business Combination, Consideration Transferred					4,052
Fixed payments [Member]
Business Acquisition [Line Items]
Business Combination, Contingent Consideration, Liability	4,790,000		$ 4,790,000		4,790,000		$ 40,370,000
Fixed payments [Member] | Aggregate 2016 Step Up Transactions [Member]
Business Acquisition [Line Items]
Business Combination, Consideration Transferred					542
Noncontrolling Interest Equity [Domain] | Aggregate 2016 Step Up Transactions [Member]
Business Acquisition [Line Items]
Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests					19,194
Common Class A [Member] | Common Stock [Member]
Business Acquisition [Line Items]
Business Acquisition, Pro Forma Net Income (Loss)
Common Class A [Member] | Common Stock [Member] | Forsman & Bodenfors AB [Domain]
Business Acquisition [Line Items]
Stock Issued During Period, Shares, Acquisitions		1,900,000
Stock Issued During Period, Value, Acquisitions	$ 21,371	$ 34,219,000			$ 34,219,000	$ 0

Accruals and Other Liabilitie37

Accruals and Other Liabilities (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Accrued and Other Liabilities [Abstract]
Net Income (Loss) Attributable to Noncontrolling Interest	$ 1,059	$ 2,122	$ 3,172	$ 7,343	$ 9,054
Payments to Noncontrolling Interests			6,549	9,462	9,503
Beginning balance			5,473	$ 6,014	6,014
Other			1,159		(92)
Ending balance	$ 3,255		$ 3,255		$ 5,473

Accruals and Other Liabilitie38

Accruals and Other Liabilities (Details Textual) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015	Dec. 31, 2014
Accrued and Other Liabilities [Abstract]
Accrued Media Cost, Current	$ 144,864	$ 187,540
Accrued and Other Liabilities Attributable To Noncontrolling Interest	$ 3,255	$ 5,473	$ 6,014

Discontinued Operations (Detail

Discontinued Operations (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015	May 31, 2015
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net loss from discontinued operations attributable to MDC Partners Inc., net of taxes	$ 0	$ (1,316,000)	$ 0	$ (6,281,000)
Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Consideration						$ 0
Discontinued Operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Revenue		0		27,025,000
Operating loss		0		(322,000)
Other expense		0		(752,000)
Loss on disposal		(1,316,000)		(5,207,000)
Net loss from discontinued operations attributable to MDC Partners Inc., net of taxes	0	$ (1,316,000)	0	$ (6,281,000)
Discontinued Operations, Held-for-sale [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Assets	$ 0		$ 0		$ 0

Debt (Details)

Debt (Details) - USD ($)	Sep. 30, 2016	Dec. 31, 2015	Sep. 30, 2015
Debt [Line Items]
Debt Issuance Costs, Net	$ (19,343,000)	$ (12,625,000)	$ (13,254,000)
Revolving credit agreement	70,497,000	0
Debt Instrument, Unamortized Premium	0	5,838,000
Debt, Long-term and Short-term, Combined Amount, Total	951,154,000	728,213,000
Obligations under capital leases	293,000	670,000
Debt and Capital Lease Obligations	951,447,000	728,883,000
Less current portion:	260,000	470,000
Long-term Debt, Excluding Current Maturities, Total	951,187,000	728,413,000
Notes due 2024 [Domain]
Debt [Line Items]
Senior Notes	900,000,000	0
Notes due 2020 [Member]
Debt [Line Items]
Senior Notes	$ 0	$ 735,000,000

Debt (Details Textual)

Debt (Details Textual) - USD ($)	May 01, 2024	May 03, 2016	Mar. 23, 2016	Oct. 23, 2014	Mar. 20, 2013	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	May 01, 2019	Dec. 31, 2015
Debt [Line Items]
Debt Issuance Costs, Net						$ 19,343,000	$ 13,254,000	$ 19,343,000	$ 13,254,000		$ 12,625,000
Long-term Line of Credit, Noncurrent						70,497,000		70,497,000			0
Loss on redemption of notes						0	$ 0	(33,298,000)	0
Debt Instrument, Unamortized Premium						0		0			5,838,000
Interest Paid								27,979,000	$ 26,358,000
Letters of Credit Outstanding, Amount						4,597,000		4,597,000
Outstanding Checks						$ 56,026,000		$ 56,026,000			73,558,000
Six Point Five Zero Percentage Notes [Domain]
Debt [Line Items]
Debt Instrument, Face Amount			$ 900,000
Debt Instrument, Interest Rate, Stated Percentage			6.50%			6.50%		6.50%
Proceeds from Offering			$ 880,000
Debt Instrument, Redemption Date, One								May 1, 2019
Debt Instrument, Redemption Date, Two								May 1, 2020
Debt Instrument, Percentage Of Redemption Price, Redemption Date Three								101.625%
Debt Instrument, Redemption Date, Three								May 1, 2021
Debt Instrument, Redemption Date, Latest For Redemption At Face Amount								May 1, 2022
Debt Instrument, Percentage Of Redemption Price, Redemption Date One								104.875%
Debt Instrument, Percentage Of Redemption Price, Redemption Date Two								103.25%
Debt Instrument, Percentage Of Redemption Price, Redemption Date, Latest For Redemption At Face Amount								100.00%
Debt Instrument, Percentage Redeemable Redemption Date, Additional								106.50%
Debt Instrument, Percentage Of Redemption Price, Change In Ownership Control								101.00%
Notes due 2024 [Domain]
Debt [Line Items]
Senior Notes						$ 900,000,000		$ 900,000,000			0
Debt Instrument, Interest Rate, Stated Percentage						6.50%		6.50%
Notes due 2020 [Member]
Debt [Line Items]
Senior Notes						$ 0		$ 0			$ 735,000,000
Debt Instrument, Interest Rate, Stated Percentage						6.75%		6.75%
6.75% Notes
Debt [Line Items]
Debt Instrument, Interest Rate, Stated Percentage					6.75%
Loss on redemption of notes								$ 33,298
Debt Instrument, Percentage Of Redemption Price, Redemption Date One			103.375%
Wells Fargo Capital Finance, LLC
Debt [Line Items]
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage		0.25%
Line of Credit Facility, Increase (Decrease), Net				$ 100,000,000
Long-term Line of Credit					$ 225,000,000
Debt Instrument, Maturity Date		May 3, 2021		Sep. 30, 2019
Debt Instrument, Face Amount				$ 325,000,000
Line of Credit Facility, Description					Dec. 31, 2018
Wells Fargo Capital Finance, LLC | Base Rate
Debt [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		0.75%		1.00%
Wells Fargo Capital Finance, LLC | London Interbank Offered Rate (LIBOR)
Debt [Line Items]
Debt Instrument, Interest Rate, Stated Percentage				1.75%
Wells Fargo Capital Finance, LLC | Non-Prime Rate and Prime Rate on European Advances [Member]
Debt [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		1.50%
Wells Fargo Capital Finance, LLC | 6.75% Notes
Debt [Line Items]
Debt Instrument, Maturity Date			Apr. 1, 2020
Scenario, Forecast [Member] | Six Point Five Zero Percentage Notes [Domain]
Debt [Line Items]
Debt Instrument, Maturity Date	May 1, 2024
Scenario, Forecast [Member] | Wells Fargo Capital Finance, LLC | Six Point Five Zero Percentage Notes [Domain]
Debt [Line Items]
Debt Instrument, Maturity Date	May 1, 2024
Scenario, Forecast [Member] | Optional redemption [Domain] | Six Point Five Zero Percentage Notes [Domain]
Debt [Line Items]
Debt Instrument, Percentage Of Redemption Price Redemption Date, Additional										35.00%

Fair Value Measurements (Detail

Fair Value Measurements (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Business Combination, Contingent Consideration, Liability	$ 243,097	$ 347,104
Fair Value, Inputs, Level 1 | Six Point Five Zero Percentage Notes [Domain]
Liabilities:
Long term debt, Carrying Amount	900,000	0
Long term debt, Fair Value	832,500	0
Fair Value, Inputs, Level 1 | 6.75% Notes
Liabilities:
Long term debt, Carrying Amount	0	740,838
Long term debt, Fair Value	$ 0	$ 765,319

Fair Value Measurements (Deta43

Fair Value Measurements (Details 1) - Fair Value, Inputs, Level 3 - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2016	Dec. 31, 2015
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning Balance of contingent payments	$ 306,734	$ 172,227
Payments	(100,667)	(77,301)
Grants	16,132	174,530
Redemption value adjustments	21,131	41,636
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Other Adjustments	(6,412)	0
Foreign translation adjustment	1,389	(4,358)
Ending Balance of contingent payments	$ 238,307	$ 306,734

Fair Value Measurements (Deta44

Fair Value Measurements (Details Textual) - USD ($) $ in Thousands	9 Months Ended		12 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Stock Issued During Period, Value, Restricted Stock Award, Net of Forfeitures	$ 0
Business Combination, Contingent Consideration, Liability	243,097		$ 347,104
Fair Value, Inputs, Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Other Adjustments	(6,412)		0
Fixed payments [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Business Combination, Contingent Consideration, Liability	4,790		40,370
Common Stock [Member] | Common Class A [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Stock Issued During Period, Value, New Issues	$ 10,458	$ 0
Stock Issued During Period, Shares, New Issues	691,559
Share Capital To Be Issued [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Common Stock, Value, To be Issued	$ 2,360
Common Stock, Shares, To be Issued	100,000
Stock Issued During Period, Value, Restricted Stock Award, Net of Forfeitures	$ 0
Stock Issued During Period, Shares, Restricted Stock Award, Net of Forfeitures	0
Share Capital To Be Issued [Member] | Common Class A [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Stock Authorized During Period, Value, To be Issued	$ 2,360
Common Stock, Value, To be Issued	$ 2,360		$ 0
Stock Authorized During Period, Shares, To be Issued	100,000
Common Stock, Shares, To be Issued	100,000		0
Contingent Consideration, Liability Settlements [Domain]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Stock Issued During Period, Value, New Issues	$ 12,818

Other Income (Expense) (Details

Other Income (Expense) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Other Income and Expenses [Abstract]
Foreign Currency Transaction Gain (Loss), before Tax	$ (5,916)	$ (15,627)	$ 9,868	$ (29,797)
Other Expense Disclosure, Nonoperating	26	4	(220)	482
Gain (Loss) on Disposition of Business	$ (800)	$ 0	$ (800)	$ 0
Gain (Loss) on Investments	$ 682	$ 0	$ 682	$ 0

Segment Information (Details)

Segment Information (Details) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2016USD ($)	Sep. 30, 2015USD ($)	Sep. 30, 2016USD ($)segment	Sep. 30, 2015USD ($)	Dec. 31, 2015USD ($)
Segment Reporting Information [Line Items]
Number of Reportable Segments | segment			1
Revenue	$ 349,254	$ 328,415	$ 995,343	$ 967,243
Cost of services sold	235,659	212,925	675,940	648,386
Office and general expenses	83,303	78,786	233,840	206,169
Depreciation and amortization	11,412	13,086	34,068	39,393
Goodwill, Impairment Loss	29,631	0	29,631	0
Operating profit	(10,751)	23,618	21,864	73,295
Other Income (Expense):
Other income, net	(6,008)	(15,623)	9,530	(29,315)
Interest expense, net	(16,322)	(14,524)	(48,690)	(42,684)
Loss On Redemption Of Notes	0	0	(33,298)	0
Loss from continuing operations before income taxes, equity in affiliates	(33,081)	(6,529)	(50,594)	1,296
Income tax benefit	(540)	(1,191)	1,893	(566)
Loss from continuing operations before equity in affiliates	(32,541)	(5,338)	(52,487)	1,862
Equity in earnings of non-consolidated affiliates	70	172	9	627
Income from continuing operations	(32,471)	(5,166)	(52,478)	2,489
Loss from discontinuing operations attributable to MDC Partners Inc., net of taxes	0	(1,316)	0	(6,281)
Net loss	(32,471)	(6,482)	(52,478)	(3,792)
Net income attributable to the noncontrolling interests	(1,059)	(2,122)	(3,172)	(7,343)	$ (9,054)
Net loss attributable to MDC Partners Inc.	(33,530)	(8,604)	(55,650)	(11,135)
Stock-based compensation	5,228	3,266	15,443	13,025
Supplemental Segment Information:
Capital expenditures	6,275	8,161	19,723	17,665
Goodwill and intangibles	961,458	944,702	961,458	944,702
Total Assets	1,642,312	1,603,946	1,642,312	1,603,946	$ 1,577,625
Corporate
Segment Reporting Information [Line Items]
Revenue	0	0	0	0
Cost of services sold	0	0	0	0
Office and general expenses	6,692	19,464	31,716	49,273
Depreciation and amortization	359	337	1,266	1,236
Goodwill, Impairment Loss	0		0
Operating profit	(7,051)	(19,801)	(32,982)	(50,509)
Other Income (Expense):
Net income attributable to the noncontrolling interests	0	0	0	0
Stock-based compensation	605	606	2,059	2,002
Supplemental Segment Information:
Capital expenditures	0	10	32	273
Goodwill and intangibles	0	0	0	0
Total Assets	135,698	124,146	135,698	124,146
Reportable Segment [Domain]
Segment Reporting Information [Line Items]
Revenue	289,988	271,882	822,762	804,399
Cost of services sold	193,677	173,944	558,854	535,278
Office and general expenses	65,407	50,425	171,310	137,403
Depreciation and amortization	10,070	8,095	24,462	24,486
Goodwill, Impairment Loss	0		0
Operating profit	20,834	39,418	68,136	107,232
Other Income (Expense):
Net income attributable to the noncontrolling interests	(962)	(1,366)	(2,604)	(6,010)
Stock-based compensation	3,337	1,857	11,067	7,763
Supplemental Segment Information:
Capital expenditures	5,938	7,650	17,440	16,084
Goodwill and intangibles	751,511	695,839	751,511	695,839
Total Assets	1,214,533	1,155,558	1,214,533	1,155,558
All Other Segment [Domain]
Segment Reporting Information [Line Items]
Revenue	59,266	56,533	172,581	162,844
Cost of services sold	41,982	38,981	117,086	113,108
Office and general expenses	11,204	8,897	30,814	19,493
Depreciation and amortization	983	4,654	8,340	13,671
Goodwill, Impairment Loss	29,631		29,631
Operating profit	(24,534)	4,001	(13,290)	16,572
Other Income (Expense):
Net income attributable to the noncontrolling interests	(97)	(756)	(568)	(1,333)
Stock-based compensation	1,286	803	2,317	3,260
Supplemental Segment Information:
Capital expenditures	337	501	2,251
Goodwill and intangibles	209,947	248,863	209,947	248,863
Total Assets	$ 292,081	$ 324,242	$ 292,081	$ 324,242

Segment Information (Details 1)

Segment Information (Details 1) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Segment Reporting Information [Line Items]
Revenue	$ 349,254	$ 328,415	$ 995,343	$ 967,243
United States
Segment Reporting Information [Line Items]
Revenue	274,506	270,512	799,696	793,904
Canada
Segment Reporting Information [Line Items]
Revenue	30,233	29,559	92,253	94,817
Other Regions [Domain]
Segment Reporting Information [Line Items]
Revenue	$ 44,515	$ 28,344	$ 103,394	$ 78,522

Segment Information Additional

Segment Information Additional Information (Details)	9 Months Ended
	Sep. 30, 2016segment
Segment Reporting Information [Line Items]
Number of Reportable Segments	1

Commitments, Contingencies an49

Commitments, Contingencies and Guarantees (Details Textual) - USD ($)	Dec. 31, 2015	Aug. 07, 2015	Dec. 31, 2015	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Other Commitments [Line Items]
Redeemable Noncontrolling Interest, Equity, Fair Value	$ 69,471,000		$ 69,471,000		$ 60,174,000		$ 60,174,000
Initial Perquisites Repayment	$ 11,285
Bonus Repayment		$ 10,582	$ 1,500	$ 1,000
Non-recoverable cash bonus award charge						$ 5,338
Investment Commitments					891,000		891,000
Letters of Credit Outstanding, Amount					4,597,000		$ 4,597,000
Minimum [Member]
Other Commitments [Line Items]
Redeemable noncontrolling interest obligation, year of payment							2,016
Maximum [Member]
Other Commitments [Line Items]
Redeemable noncontrolling interest obligation, year of payment							2,024
Contractual redemption right [Member]
Other Commitments [Line Items]
Redeemable Noncontrolling Interest, Equity, Redemption Value					13,324,000		$ 13,324,000
Contractual redemption right [Domain] | Common Class A [Member]
Other Commitments [Line Items]
Redeemable Noncontrolling Interest, Equity, Redemption Value					126,000		126,000
Excess initial redemption value [Domain]
Other Commitments [Line Items]
Redeemable Noncontrolling Interest, Equity, Redemption Value					3,060,000		3,060,000
Termination or death redemption right [Domain]
Other Commitments [Line Items]
Redeemable Noncontrolling Interest, Equity, Redemption Value					43,790,000		43,790,000
SEC Investigation [Member]
Other Commitments [Line Items]
Professional Fees					$ 2,463	$ 2,722	$ 725	$ 12,366

Subsequent Events and Other (De

Subsequent Events and Other (Details)	May 03, 2016	Oct. 23, 2014
Wells Fargo Capital Finance, Llc [Member]
Subsequent Event [Line Items]
Debt Instrument, Maturity Date	May 3, 2021	Sep. 30, 2019

Goodwill and Intangible Assets

Goodwill and Intangible Assets (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015	Dec. 31, 2014
Goodwill [Line Items]
Goodwill	$ 868,483		$ 868,483		$ 870,301	$ 851,372
Goodwill, Acquired During Period			24,778		43,655
Goodwill, Written off Related to Sale of Business Unit	(764)		764
Goodwill, Impairment Loss	(29,631)	$ 0	(29,631)	$ 0
Goodwill, Purchase Accounting Adjustments					(2,428)
Goodwill, Foreign Currency Translation Gain (Loss)			3,799		(22,298)
Reportable Segment [Domain]
Goodwill [Line Items]
Goodwill	680,168		680,168		655,039	660,792
Goodwill, Acquired During Period			24,778		6,254
Goodwill, Written off Related to Sale of Business Unit			0
Goodwill, Impairment Loss	0		0
Goodwill, Purchase Accounting Adjustments					(1,744)
Goodwill, Foreign Currency Translation Gain (Loss)			351		(10,263)
All Other Segment [Domain]
Goodwill [Line Items]
Goodwill	188,315		188,315		215,262	$ 190,580
Goodwill, Acquired During Period			0		37,401
Goodwill, Written off Related to Sale of Business Unit			(764)
Goodwill, Impairment Loss	$ (29,631)		(29,631)
Goodwill, Purchase Accounting Adjustments					(684)
Goodwill, Foreign Currency Translation Gain (Loss)			$ 3,448		$ (12,035)

Goodwill and Intangible Asset52

Goodwill and Intangible Assets (Details Textual) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Goodwill [Line Items]
Goodwill, Impairment Loss	$ 29,631	$ 0	$ 29,631	$ 0
All Other Segment [Domain]
Goodwill [Line Items]
Goodwill, Impairment Loss	$ 29,631		29,631
All Other Segment [Domain] | Experiential [Member]
Goodwill [Line Items]
Goodwill, Impairment Loss			28
All Other Segment [Domain] | Immaterial [Member]
Goodwill [Line Items]
Goodwill, Impairment Loss			$ 2