Loan Receivables and Allowance for Credit Losses - Loans Entered into a Loan Modification Program (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, modified, weighted average interest rate decrease from modification	97.00%	97.00%	97.00%
Modification Date Amount
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans entered into a modification program	$ 2,486	$ 2,702	$ 2,208
% of Total Class of Loan Receivables	2.40%	2.60%	2.10%
Credit cards \| Long-term Modification \| Modification Date Amount
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans entered into a modification program	$ 1,608	$ 1,743	$ 1,573
% of Total Class of Loan Receivables	1.70%	1.80%	1.60%
Credit cards \| Short-term Modification \| Modification Date Amount
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans entered into a modification program	$ 867	$ 948	$ 628
% of Total Class of Loan Receivables	0.90%	1.00%	0.60%
Consumer installment loans \| Long-term Modification \| Modification Date Amount
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans entered into a modification program	$ 0	$ 0	$ 0
% of Total Class of Loan Receivables	0.00%	0.00%	0.00%
Consumer installment loans \| Short-term Modification \| Modification Date Amount
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans entered into a modification program	$ 0	$ 0	$ 0
% of Total Class of Loan Receivables	0.00%	0.00%	0.00%
Commercial credit products \| Long-term Modification \| Modification Date Amount
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans entered into a modification program	$ 9	$ 10	$ 6
% of Total Class of Loan Receivables	0.50%	0.50%	0.30%
Commercial credit products \| Short-term Modification \| Modification Date Amount
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans entered into a modification program	$ 2	$ 1	$ 1
% of Total Class of Loan Receivables	0.00%	0.00%	0.00%

Synchrony Financial 10-K