Loans and Accounts Receivable (Details 3)	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
Global Consumer Services Group [Member] | Card Member Loans [Member] | Net Write-Off Rate - Principal Only [Member]
Credit Quality Indicator for Loans and Receivables
Credit Quality Indicators	2.40%	2.10%
Global Consumer Services Group [Member] | Card Member Loans [Member] | Net Write-Off Rate Principal Interest, and Fees [Member]
Credit Quality Indicator for Loans and Receivables
Credit Quality Indicators	2.80%	2.50%
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	1.40%	1.30%
Global Consumer Services Group [Member] | Card Member Receivables [Member] | Net Write-Off Rate - Principal Only [Member]
Credit Quality Indicator for Loans and Receivables
Credit Quality Indicators	1.70%	1.60%
Global Consumer Services Group [Member] | Card Member Receivables [Member] | Net Write-Off Rate Principal Interest, and Fees [Member]
Credit Quality Indicator for Loans and Receivables
Credit Quality Indicators	1.80%	1.80%
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	1.30%	1.20%
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	1.80%	1.70%
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	2.10%	2.00%
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	1.30%	1.20%
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	1.80%	1.90%
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	2.10%	2.10%
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	1.60%	1.40%
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	0.07%	0.11%
Global Corporate Payments [Member] | Card Member Receivables [Member] | 90 days past billing as a percentage of receivables [Member}
Credit Quality Indicator for Loans and Receivables
Credit Quality Indicators	0.70%	0.80%