v3.7.0.1
Significant Customer Concentrations (Details) - Customer Concentration Risk [Member] - Walmart [Member]
3 Months Ended
Mar. 31, 2017
Mar. 31, 2016
Dec. 31, 2016
Total Operating Revenues [Member]      
Concentration Risk [Line Items]      
Concentration risk, percentage 37.00% 36.00%  
Settlement Assets [Member]      
Concentration Risk [Line Items]      
Concentration risk, percentage (balance sheet disclosures) 36.00%   42.00%