XML 134 R120.htm IDEA: XBRL DOCUMENT v3.10.0.1
Legal & Regulatory Proceedings (Legal and Regulatory Proceedings - Additional Information) (Detail)
$ in Millions
3 Months Ended 12 Months Ended
Sep. 30, 2018
USD ($)
Mar. 31, 2013
USD ($)
Dec. 31, 2013
Sep. 30, 2015
USD ($)
Sep. 30, 2012
Mar. 31, 2012
USD ($)
Loss Contingencies            
Amount in excess of amounts reserved $ 9          
APR Percentage Allegedly Misleading         120.00%  
Number Of Putative Class Actions Filed     4      
Damages Claimed By Plaintiff       $ 800   $ 40
Federal Lawsuits            
Loss Contingencies            
Number of merchants requesting exclusion   500        
Class Action Settlement            
Loss Contingencies            
Number of merchants requesting exclusion   8,000        
Percentage of escrow funds returned to defendants   25.00%        
Escrow Deposit   $ 46        
Amended Settlement Agreement            
Loss Contingencies            
Litigation Settlement Amount Awarded To Other Party 6,240          
Escrow Funds Returned Defendants 700          
Litigation Settlement Amount Awarded To Other Party, Escrow 5,300          
Litigation Settlement Amount Awarded To Other Party, Additional $ 900