Card Member Receivables and Card Member Loans (Details 3)	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Global Consumer Services Group [Member] | Card Member Receivables [Member] | Net Write-Off Rate [Member]
Credit Quality Indicator for Loans and Receivables
Credit Quality Indicators	1.11%	1.20%
Global Consumer Services Group [Member] | Card Member Receivables [Member] | 30 Days Past Due as a % of Total [Member]
Credit Quality Indicator for Loans and Receivables
Credit Quality Indicators	1.65%	0.70%
Global Consumer Services Group [Member] | Card Member Loans [Member] | Net Write-Off Rate [Member]
Credit Quality Indicator for Loans and Receivables
Credit Quality Indicators	1.78%	1.25%
Global Consumer Services Group [Member] | Card Member Loans [Member] | 30 Days Past Due as a % of Total [Member]
Credit Quality Indicator for Loans and Receivables
Credit Quality Indicators	1.49%	0.78%
Global Small Business Services [Member] | Card Member Receivables [Member] | Net Write-Off Rate [Member]
Credit Quality Indicator for Loans and Receivables
Credit Quality Indicators	1.60%	1.47%
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	1.66%	1.00%
Global Corporate Payments [Member] | Card Member Receivables [Member] | Net Write-Off Rate [Member]
Credit Quality Indicator for Loans and Receivables
Credit Quality Indicators	0.97%
Global Corporate Payments [Member] | Card Member Receivables [Member] | Net Loss Ratio as a % of Charge Volume [Member]
Credit Quality Indicator for Loans and Receivables
Credit Quality Indicators		0.06%
Global Corporate Payments [Member] | Card Member Receivables [Member] | 90 Days Past Billing as a % of Receivables [Member]
Credit Quality Indicator for Loans and Receivables
Credit Quality Indicators	1.66%	0.63%