Restructuring Costs - Additional Information (Details) (USD $)
3 Months Ended
Mar. 31, 2015
Mar. 31, 2014
Restructuring Cost And Reserve [Line Items]    
Restructuring costs $ 24,000 $ 30,343,000
Global workforce elimination percentage under restructuring plan 6.00%  
January 2014 Restructuring    
Restructuring Cost And Reserve [Line Items]    
Accumulated Restructuring Costs $ 40,400,000