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Loans - Additional Information (Details) - USD ($) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2022 | Mar. 31, 2021 | Dec. 31, 2021
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Accrued interest receivable | $ 1,300 |  | $ 1,200
TDRs | 1,900 |  | 1,600
Commitments to lend on loans modified in TDRs | 156 |  | 168
Loans held for sale | 1,155 |  | 5,888
Federal Home Loan banks |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Loans Pledged as Collateral | 10,300 |  | 10,300
Line of Credit Facility, Remaining Borrowing Capacity | 18,600 |  | 19,700
Federal Reserve Discount Window |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Loans Pledged as Collateral | 32,600 |  | 26,500
Line of Credit Facility, Remaining Borrowing Capacity | 22,900 |  | 19,600
Credit Card and Consumer Banking | Performing |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
TDRs | 1,200 |  | 1,100
Commercial Banking | Performing |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
TDRs | 299 |  | $ 192
Domestic credit card: | Domestic Credit Card and Commercial Banking Portfolios [Member] |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Revolving loans converted to term during period | $ 291 | $ 97 |

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- Definition Amount of financing receivable modified as troubled debt restructuring. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953676-111524 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 40 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=121585226&loc=d3e18845-111554 + Details
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