Loss Per Common Share (Details) (USD $)
In Thousands, except Share data, unless otherwise specified
 3 Months Ended
Mar. 31, 2015
Mar. 31, 2014
Numerator    
Numerator for basic loss per common share - loss from continuing operations $ (23,417) $ (7,213)
Net income attributable to the noncontrolling interests (2,380) (1,362)
Net loss attributable to MDC Partners Inc. common shareholders from continuing operations (25,797) (8,575)
Effect of dilutive securities 0 0
Numerator for diluted loss per common share - loss attributable to MDC Partners Inc. common shareholders from continuing operations $ (25,797) $ (8,575)
Denominator    
Denominator for basic loss per common share - weighted average common shares 49,754,961 49,338,332
Effect of dilutive securities 0 0
Denominator for diluted loss per common share - adjusted weighted shares and assumed conversions 49,754,961 49,338,332
Income (loss) from continuing operations attributable to MDC Partners Inc. common shareholders (usd per share) $ (0.52) $ (0.17)
Income (loss) from continuing operations attributable to MDC Partners Inc. common shareholders (usd per share) $ (0.52) $ (0.17)