Loans and Card Member Receivables - Credit Quality (Details 2)	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Credit Quality Indicator for Loans and Receivables
90+ Days Past Billing as a % of total	0.50%	0.40%
Card Member Loans | Consumer
Credit Quality Indicator for Loans and Receivables
30+ Days Past Due as a % of Total	1.10%	0.70%
Card Member Loans | Small Business
Credit Quality Indicator for Loans and Receivables
30+ Days Past Due as a % of Total	1.20%	0.60%
Card Member Loans | Net Write-Off Rate - Principal Only | Consumer
Credit Quality Indicator for Loans and Receivables
Net Write-Off Rate	1.70%	0.80%
Card Member Loans | Net Write-Off Rate - Principal Only | Small Business
Credit Quality Indicator for Loans and Receivables
Net Write-Off Rate	1.40%	0.60%
Card Member Loans | Net Write-Off Rate Principal Interest, and Fees | Consumer
Credit Quality Indicator for Loans and Receivables
Net Write-Off Rate	2.10%	1.10%
Card Member Loans | Net Write-Off Rate Principal Interest, and Fees | Small Business
Credit Quality Indicator for Loans and Receivables
Net Write-Off Rate	1.60%	0.70%
Card Member Receivables | Consumer
Credit Quality Indicator for Loans and Receivables
30+ Days Past Due as a % of Total	1.00%	0.80%
Card Member Receivables | Small Business
Credit Quality Indicator for Loans and Receivables
30+ Days Past Due as a % of Total	1.50%	0.90%
Card Member Receivables | Net Write-Off Rate - Principal Only | Consumer
Credit Quality Indicator for Loans and Receivables
Net Write-Off Rate	1.60%	0.60%
Card Member Receivables | Net Write-Off Rate - Principal Only | Small Business
Credit Quality Indicator for Loans and Receivables
Net Write-Off Rate	2.20%	0.80%
Card Member Receivables | Net Write-Off Rate Principal Interest, and Fees | Consumer
Credit Quality Indicator for Loans and Receivables
Net Write-Off Rate	1.70%	0.60%
Card Member Receivables | Net Write-Off Rate Principal Interest, and Fees | Small Business
Credit Quality Indicator for Loans and Receivables
Net Write-Off Rate	2.40%	0.90%
Card Member Receivables | Net Write-Off Rate Principal Interest, and Fees | Corporate
Credit Quality Indicator for Loans and Receivables
Net Write-Off Rate	0.60%	0.30%