Card Member Receivables and Card Member Loans 3 (Details)	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
Global Consumer Services Group [Member] | Card Member Receivables [Member] | Net Write-Off Rate [Member]
Credit Quality Indicator for Receivables and Loans
Credit Quality Indicators	0.0111	0.013
Global Consumer Services Group [Member] | Card Member Receivables [Member] | 30+ Days Past Due as a % of Total [Member]
Credit Quality Indicator for Receivables and Loans
Credit Quality Indicators	0.0065	0.0075
Global Consumer Services Group [Member] | Card Member Loans [Member] | Net Write-Off Rate [Member]
Credit Quality Indicator for Receivables and Loans
Credit Quality Indicators	0.0155	0.0106
Global Consumer Services Group [Member] | Card Member Loans [Member] | 30+ Days Past Due as a % of Total [Member]
Credit Quality Indicator for Receivables and Loans
Credit Quality Indicators	0.009	0.0069
Global Small Business Services [Member] | Card Member Receivables [Member] | Net Write-Off Rate [Member]
Credit Quality Indicator for Receivables and Loans
Credit Quality Indicators	0.0136	0.0156
Global Small Business Services [Member] | Card Member Receivables [Member] | 30+ Days Past Due as a % of Total [Member]
Credit Quality Indicator for Receivables and Loans
Credit Quality Indicators	0.0094	0.0098
Global Corporate Payments [Member] | Card Member Receivables [Member] | Net Loss Ratio as a % of Charge Volume [Member]
Credit Quality Indicator for Receivables and Loans
Credit Quality Indicators	0.0006	0.0007
Global Corporate Payments [Member] | Card Member Receivables [Member] | 90+ days past billing as a percentage of receivables [Member]
Credit Quality Indicator for Receivables and Loans
Credit Quality Indicators	0.0066	0.0081