Card Member Receivables and Loans (Details 3)	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
U.S. Consumer Services [Member] | Card Member Receivables [Member] | Net Write-Off Rate [Member]
Credit Quality Indicator for Receivables and Loans
Credit Quality Indicators	0.0111	0.0057
U.S. Consumer 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	0.0084	0.0078
International Consumer and Network Services [Member] | Card Member Receivables [Member] | Net Write-Off Rate [Member]
Credit Quality Indicator for Receivables and Loans
Credit Quality Indicators	0.016	0.0182
International Consumer and Network 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	0.0139	0.0122
International Consumer and Network Services [Member] | Card Member Loans [Member] | Net Write-Off Rate [Member]
Credit Quality Indicator for Receivables and Loans
Credit Quality Indicators	0.014	0.0084
International Consumer and Network Services [Member] | Card Member Loans [Member] | 30 Days Past Due as a % of Total [Member]
Credit Quality Indicator for Receivables and Loans
Credit Quality Indicators	0.0089	0.0087
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	0.0007	0.0008
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	0.0086	0.0074
Global Small Business Services [Member] | Card Member Receivables [Member] | Net Write-Off Rate [Member]
Credit Quality Indicator for Receivables and Loans
Credit Quality Indicators	0.0142	0.0088
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	0.013	0.0118