Loans and Accounts Receivable (Details 3)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
U S Consumer Services [Member] | Card Member Loans [Member] | Net Write-Off Rate - Principal Only [Member]
Credit Quality Indicator for Loans and Receivables
Credit Quality Indicators	0.018	0.015
U S Consumer Services [Member] | Card Member Loans [Member] | Net Write-Off Rate Principal Interest, and Fees [Member]
Credit Quality Indicator for Loans and Receivables
Credit Quality Indicators	0.021	0.018
U S Consumer Services [Member] | Card Member Loans [Member] | 30 Days Past Due as a % of Total [Member]
Credit Quality Indicator for Loans and Receivables
Credit Quality Indicators	0.013	0.011
U S Consumer Services [Member] | Card Member Receivables [Member] | Net Write-Off Rate - Principal Only [Member]
Credit Quality Indicator for Loans and Receivables
Credit Quality Indicators	0.013	0.014
U S Consumer Services [Member] | Card Member Receivables [Member] | Net Write-Off Rate Principal Interest, and Fees [Member]
Credit Quality Indicator for Loans and Receivables
Credit Quality Indicators	0.014	0.016
U S Consumer Services [Member] | Card Member Receivables [Member] | 30 Days Past Due as a % of Total [Member]
Credit Quality Indicator for Loans and Receivables
Credit Quality Indicators	0.011	0.012
International Consumer and Network Services [Member] | Card Member Loans [Member] | Net Write-Off Rate - Principal Only [Member]
Credit Quality Indicator for Loans and Receivables
Credit Quality Indicators	0.021	0.02
International Consumer and Network Services [Member] | Card Member Loans [Member] | Net Write-Off Rate Principal Interest, and Fees [Member]
Credit Quality Indicator for Loans and Receivables
Credit Quality Indicators	0.025	0.025
International Consumer and Network Services [Member] | Card Member Loans [Member] | 30 Days Past Due as a % of Total [Member]
Credit Quality Indicator for Loans and Receivables
Credit Quality Indicators	0.014	0.016
International Consumer and Network Services [Member] | Card Member Receivables [Member] | Net Write-Off Rate - Principal Only [Member]
Credit Quality Indicator for Loans and Receivables
Credit Quality Indicators	0.02	0.02
International Consumer and Network Services [Member] | Card Member Receivables [Member] | Net Write-Off Rate Principal Interest, and Fees [Member]
Credit Quality Indicator for Loans and Receivables
Credit Quality Indicators	0.021	0.022
International Consumer and Network Services [Member] | Card Member Receivables [Member] | 30 Days Past Due as a % of Total [Member]
Credit Quality Indicator for Loans and Receivables
Credit Quality Indicators	0.013	0.013
Global Small Business Services [Member] | Card Member Loans [Member] | Net Write-Off Rate - Principal Only [Member]
Credit Quality Indicator for Loans and Receivables
Credit Quality Indicators	0.016	0.014
Global Small Business Services [Member] | Card Member Loans [Member] | Net Write-Off Rate Principal Interest, and Fees [Member]
Credit Quality Indicator for Loans and Receivables
Credit Quality Indicators	0.019	0.017
Global Small Business Services [Member] | Card Member Loans [Member] | 30 Days Past Due as a % of Total [Member]
Credit Quality Indicator for Loans and Receivables
Credit Quality Indicators	0.012	0.011
Global Small Business Services [Member] | Card Member Receivables [Member] | Net Write-Off Rate - Principal Only [Member]
Credit Quality Indicator for Loans and Receivables
Credit Quality Indicators	0.016	0.015
Global Small Business Services [Member] | Card Member Receivables [Member] | Net Write-Off Rate Principal Interest, and Fees [Member]
Credit Quality Indicator for Loans and Receivables
Credit Quality Indicators	0.018	0.017
Global Small Business Services [Member] | Card Member Receivables [Member] | 30 Days Past Due as a % of Total [Member]
Credit Quality Indicator for Loans and Receivables
Credit Quality Indicators	0.016	0.016
Global Corporate Payments [Member] | Net Loss Ratio as a % of Charge Volume [Member]
Credit Quality Indicator for Loans and Receivables
Credit Quality Indicators	0.001	0.0009
Global Corporate Payments [Member] | 90 days past billing as a percentage of receivables [Member}
Credit Quality Indicator for Loans and Receivables
Credit Quality Indicators	0.009	0.009