CONDENSED STATEMENTS OF SHAREHOLDERS' DEFICIT - USD ($) $ in Thousands	Total	Common Stock Common Class A	Common Stock Common 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]
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.	(22,120)	$ 0	$ 0	0		0	0	(22,120)	0	(22,120)	0
Other Comprehensive income (loss)	(10,685)	$ 0	0	0		0	0	0	(12,484)	(12,484)	1,799
Stock Issued During Period, Restricted Stock and Stock Options, Net of Forfeitures		242,124
Stock Issued During Period, Value, Restricted Stock and Stock Options, Net of Forfeitures		$ 2,930
Issuance of restricted stock	0		$ 0	$ 0		(2,930)	0	0	0	0	0
Stock Issued During Period, Shares, New Issues		237,013
Stock Issued During Period, Value, New Issues		$ 5,585										$ 7,945	$ 7,945
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	(2,474)	$ (2,474)	$ 0	$ 0		0	0	0	0	(2,474)	0
Shares acquired and cancelled (in shares)		(116,786)	0	0
Stock-based compensation	5,290	$ 0	$ 0	$ 0		5,290	0	0	0	5,290	0
Changes in redemption value of redeemable noncontrolling interests		0	0	0			0	0	0		0
Temporary Equity, Accretion to Redemption Value	4,141					4,141				4,141
Noncontrolling Interest, Increase from Business Combination	3,844					23,018				23,018	(19,174)
Changes in noncontrolling interests and redeemable noncontrolling interest from step-up transactions										(19,174)
Dividends paid and to be paid	(21,581)	0	0	0		(21,581)	0	0	0	(21,581)	0
Transfer to charges in excess of capital	0	0	0	$ 0		(7,938)	7,938	0	0	0	0
Balance at Jun. 30, 2016	$ (522,713)	$ 275,882	$ 1			$ 0	$ (307,323)	$ (549,110)	$ (6,227)	$ (584,417)	$ 61,704
Balance (in shares) at Jun. 30, 2016		50,349,056	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