Commitments and Contingencies - Estimate of the Maximum Potential Exposure and Allowance for Transaction Losses Related to Protection Products (Details) - USD ($) $ in Millions |
Jun. 30, 2015 |
Dec. 31, 2014 |
Jun. 30, 2014 |
Dec. 31, 2013 |
---|---|---|---|---|
Loss Contingencies [Line Items] | ||||
Allowance for transaction losses | $ 185 | $ 195 | $ 160 | $ 146 |
Protection Programs | ||||
Loss Contingencies [Line Items] | ||||
Maximum potential exposure | 73,250 | 75,833 | ||
Allowance for transaction losses | $ 190 | $ 166 |