Loss Per Common Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Earnings Per Share [Abstract]
Income from continuing operations	$ 31,072	$ 19,555	$ 7,655	$ 12,342
Numerator
Net income attributable to the noncontrolling interests	(2,841)	(1,749)	(5,221)	(3,111)	$ (6,890)
Income (Loss) from Continuing Operations Attributable to Parent	28,231	17,806	2,434	9,231
Effect of dilutive securities	0	0	0	0
Income (Loss) from Continuing Operations Attributable to Parent, Diluted	$ 28,231	$ 17,806	$ 2,434	$ 9,231
Denominator
Denominator for basic income per common share - weighted average common shares	49,859,300	49,546,062	49,807,419	49,442,770
Effect of dilutive securities	540,636	649,259	557,700	663,775
Denominator for diluted income per common share - adjusted weighted shares and assumed conversions	50,399,936	50,195,321	50,365,119	50,106,545
Income (loss) from continuing operations attributable to MDC Partners Inc. common shareholders (usd per share)	$ 0.57	$ 0.36	$ 0.05	$ 0.19
Income (loss) from continuing operations attributable to MDC Partners Inc. common shareholders (usd per share)	$ 0.56	$ 0.35	$ 0.05	$ 0.18