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Allowance for Credit Losses - Narratives (Details) $ in Millions | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2022 loan | Dec. 31, 2021 USD ($) loan
Financing Receivable, Allowance for Credit Loss [Line Items] |  |
Number of modifications resulted in the permanent reduction | 0 |
Number of loans modified due to COVID-19 |  | 1,242
Loans modified due to COVID-19 | $ |  | $ 172
Number of loans resumed normal scheduled payments |  | 1,076
Loans resumed normal scheduled payments | $ |  | $ 168
Number of loans premodified |  | 113
Number of loans provided additional payment relief |  | 0
Minimum |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |
Period of modifications involving a reduction of stated interest rate of the loan (in years) | 12 months |
Period of modifications involving an extension of the maturity date (in years) | 12 months |
Maximum |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |
Period of modifications involving a reduction of stated interest rate of the loan (in years) | 5 years |
Period of modifications involving an extension of the maturity date (in years) | 10 years |

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- Definition Number of financing receivables premodified. + References No definition available. + Details
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- Definition Number of loans modified other than troubled debt restructurings. + References No definition available. + Details
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- Definition Number of loans provided additional payment relief. + References No definition available. + Details
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- Definition Number of financing receivable contracts modified as troubled debt restructuring within previous 12 months, with subsequent payment default. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 34 -URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953682-111524 + Details
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- Definition Amount of financing receivable modified on trial basis. + 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 + Details
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