Acquisitions (Details) (USD $)
In Thousands, unless otherwise specified
3 Months Ended 9 Months Ended
Mar. 31, 2015
Mar. 31, 2014
Sep. 30, 2014
Sep. 30, 2013
Business Combinations [Abstract]        
Net loss attributable to MDC Partners Inc. $ (32,091) $ (8,846) $ (32,091) $ (8,846)
Transfers from the noncontrolling Interest:        
Decrease in MDC Partners Inc. paid in capital for purchase of equity interests in excess of Redeemable Noncontrolling Interests and Noncontrolling Interests     (2,917) (4,798)
Net transfers from noncontrolling interest     (2,917) (4,798)
Change from net loss attributable to MDC Partners Inc. and transfers to non controlling interest     $ (35,008) $ (13,644)