CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY (DEFICIT) - USD ($)	Total	Common Class A	Common Class B	Common Stock Common Class A	Common Stock Common Class B	Share Capital to Be Issued	Additional Paid-in Capital	Charges in Excess of Capital	Retained Earnings [Member]	Stock Subscription Receivable	Accumulated Other Comprehensive Loss	MDC Partners Inc. Shareholders’ Deficit	Noncontrolling Interests	Forsman & Bodenfors AB [Domain] Common Stock Common Class A	Contingent Consideration Classified as Equity [Member] MDC Partners Inc. Shareholders’ Deficit	Contingent Consideration, Liability Settlements [Domain]	Contingent Consideration, Liability Settlements [Domain] MDC Partners Inc. Shareholders’ Deficit
Stock Issued During Period, Value, Restricted Stock Award, Net of Forfeitures	$ 0			$ 7,661,000			$ (7,661,000)
Noncontrolling Interest, Increase from Business Combination	50,118,000												$ 50,118,000
Stockholders' equity, beginning balance at Dec. 31, 2013	(290,180,000)			$ 262,655,000	$ 1,000	$ 424,000	0	$ (126,352,000)	$ (479,144,000)	$ (55,000)	$ (797,000)	$ (343,268,000)	53,088,000
Common stock outstanding, beginning balance (in shares) at Dec. 31, 2013				49,092,427	3,755	42,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss attributable to MDC Partners	(21,411,000)								(21,411,000)			(21,411,000)
Other comprehensive income (loss)	(8,667,000)										(6,955,000)	(6,955,000)	(1,712,000)
Shares acquired and canceled	(5,414,000)			$ (5,414,000)								(5,414,000)
Shares acquired and cancelled (in shares)				(216,004)
Stock subscription receipts	55,000									55,000		55,000
Stock-based compensation	9,868,000						9,868,000					9,868,000
Noncontrolling Interest, Change in Redemption Value							(38,850,000)					(38,850,000)
Temporary Equity, Accretion to Redemption Value	(38,850,000)
Dividends paid and to be paid	(37,244,000)						(37,244,000)					(37,244,000)
Other	54,000			$ 915,000		$ (424,000)	(437,000)					54,000
Other (in shares)				42,000		(42,000)
Transfer to charges in excess of capital	0						83,316,000	(83,316,000)
Common stock outstanding, ending balance (in shares) at Dec. 31, 2014				49,680,109	3,755	0
Stockholders' equity, ending balance at Dec. 31, 2014	(359,502,000)			$ 265,817,000	$ 1,000	$ 0	0	(209,668,000)	(500,555,000)	0	(7,752,000)	(452,157,000)	92,655,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock Issued During Period, Shares, Restricted Stock Award, Net of Forfeitures				761,686
Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests	$ (17,831,000)						(8,992,000)					(8,992,000)	(8,839,000)
Stock Issued During Period, Shares, New Issues	0
Stock Issued During Period, Value, New Issues				$ 0
Stock Issued During Period, Value, Acquisitions														$ 0
Stock Issued During Period, Value, Restricted Stock Award, Net of Forfeitures	$ 0			6,069,000			(6,069,000)
Noncontrolling Interest, Increase from Business Combination	(51,488,000)						(42,780,000)					(42,780,000)	(8,708,000)
Net loss attributable to MDC Partners	(35,454,000)											(35,454,000)
Other comprehensive income (loss)	9,141,000										14,009,000	14,009,000	(4,868,000)
Shares acquired and canceled	(2,388,000)			$ (2,388,000)								(2,388,000)
Shares acquired and cancelled (in shares)				(96,777)
Options Exercised	224,000			$ 343,000			(119,000)					224,000
Options Exercised (in shares)				37,500
Stock-based compensation	8,437,000						8,437,000					8,437,000
Temporary Equity, Accretion to Redemption Value	(22,809,000)						(22,809,000)					(22,809,000)
Dividends paid and to be paid	(42,253,000)						(42,253,000)					(42,253,000)
Transfer to charges in excess of capital	0						105,593,000	(105,593,000)
Common stock outstanding, ending balance (in shares) at Dec. 31, 2015		49,986,705	3,755	49,986,705	3,755	0
Stockholders' equity, ending balance at Dec. 31, 2015	$ (496,092,000)			$ 269,841,000	$ 1,000	$ 0	0	(315,261,000)	(536,009,000)	0	6,257,000	(575,171,000)	79,079,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock Issued During Period, Shares, Restricted Stock Award, Net of Forfeitures				365,873
Stock Issued During Period, Shares, New Issues	0
Stock Issued During Period, Value, New Issues				$ 0
Stock Issued During Period, Value, Acquisitions														0
Noncontrolling Interest, Increase from Business Combination	$ 8,936,000						22,776,000					22,776,000	(13,840,000)
Net loss attributable to MDC Partners	(45,839,000)											(45,839,000)
Other comprehensive income (loss)	(7,687,000)										(8,081,000)	(8,081,000)	394,000
Stock Appreciation Rights Exercised (in shares)						100,000
Stock Authorized During Period, Value, To be Issued						$ 2,360,000
Issuance of restricted stock (in shares)				425,915
Stock Issued During Period, Value, Restricted Stock and Stock Options, Net of Forfeitures	0			$ 6,615,000			(6,615,000)					0
Shares acquired and canceled	(3,350,000)			$ (3,350,000)								(3,350,000)
Shares acquired and cancelled (in shares)				(205,876)
Stock-based compensation	10,662,000						10,662,000					10,662,000
Temporary Equity, Accretion to Redemption Value	9,604,000						9,604,000					9,604,000
Dividends paid and to be paid	(32,747,000)						(32,747,000)					(32,747,000)
Transfer to charges in excess of capital	0						(3,680,000)	3,680,000
Common stock outstanding, ending balance (in shares) at Dec. 31, 2016		52,798,303	3,755	52,798,303	3,755	100,000
Stockholders' equity, ending balance at Dec. 31, 2016	$ (509,476,000)			$ 317,783,000	$ 1,000	$ 2,360,000	$ 0	$ (311,581,000)	$ (581,848,000)	$ 0	$ (1,824,000)	$ (575,109,000)	$ 65,633,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock Issued During Period, Shares, New Issues	0			691,559
Stock Issued During Period, Value, New Issues				$ 10,458,000												$ 12,818,000	$ 12,818,000
Stock Issued During Period, Shares, Acquisitions				1,900,000
Stock Issued During Period, Value, Acquisitions	$ 34,219,000													$ 34,219,000	$ 34,219,000