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Loans - Additional Information (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Accrued interest receivable | $ 1,200 | $ 1,200 |
TDRs | 1,600 | 2,100 |
Commitments to lend on loans modified in TDRs | 168 | 173 |
Loans held for sale | 5,888 | 2,710 |
Commercial and multifamily real estate |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Payments for Origination of Mortgage Loans Held-for-sale | 9,100 | 10,000 | $ 9,000
Federal Home Loan banks |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Loans Pledged as Collateral | 10,300 | 14,100 |
Line of Credit Facility, Remaining Borrowing Capacity | 19,700 | 19,600 |
Federal Reserve Discount Window |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Loans Pledged as Collateral | 26,500 | 25,500 |
Line of Credit Facility, Remaining Borrowing Capacity | 19,600 | 20,000 |
Credit Card and Consumer Banking | Performing |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
TDRs | 1,100 | 1,300 |
Commercial Banking | Performing |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
TDRs | 192 | 442 |
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 | $ 223 | $ 602 |

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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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- Definition Carrying amount as of the balance sheet date of loans that have been pledged as collateral for borrowings. If the secured party has the right by contract or custom to sell or re-pledge the collateral, then the debtor reclassifies that asset and report that asset in its statement of financial position separately from other assets not so encumbered. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=66007379&loc=d3e113888-111728 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=123577603&loc=d3e5086-111524 + Details
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