Summary of Significant Accounting Policies (Details 2) (Customer concentration)
12 Months Ended
Dec. 31, 2013
Dec. 31, 2012
Dec. 31, 2011
Revenue | Customer A
     
Concentration of Revenue and Accounts Receivable      
Concentration risk percentage 13.00% 25.00% 29.00%
Revenue | Customer B
     
Concentration of Revenue and Accounts Receivable      
Concentration risk percentage 17.00% 28.00% 17.00%
Revenue | Customer C
     
Concentration of Revenue and Accounts Receivable      
Concentration risk percentage   14.00% 18.00%
Revenue | Customer E
     
Concentration of Revenue and Accounts Receivable      
Concentration risk percentage 12.00%   0.00%
Revenue | Customer F
     
Concentration of Revenue and Accounts Receivable      
Concentration risk percentage 13.00% 0.00% 0.00%
Accounts Receivable | Customer B
     
Concentration of Revenue and Accounts Receivable      
Concentration risk percentage 13.00% 25.00%  
Accounts Receivable | Customer C
     
Concentration of Revenue and Accounts Receivable      
Concentration risk percentage 0.00%    
Accounts Receivable | Customer D
     
Concentration of Revenue and Accounts Receivable      
Concentration risk percentage 15.00% 12.00%  
Accounts Receivable | Customer E
     
Concentration of Revenue and Accounts Receivable      
Concentration risk percentage 14.00% 40.00%  
Accounts Receivable | Customer F
     
Concentration of Revenue and Accounts Receivable      
Concentration risk percentage 41.00% 0.00%