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Loans - TDR - Subsequent Defaults of Completed TDR Modifications (Detail) $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2020 USD ($) Contract | Mar. 31, 2019 USD ($) Contract
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Number of Contracts | Contract | 30,025 | 31,846
Total Loans | $ | $ 92 | $ 70
Credit Card |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Number of Contracts | Contract | 28,743 | 30,733
Total Loans | $ | $ 48 | $ 57
Consumer Banking |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Number of Contracts | Contract | 1,276 | 1,113
Total Loans | $ | $ 16 | $ 13
Consumer Banking | Auto |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Number of Contracts | Contract | 1,275 | 1,105
Total Loans | $ | $ 16 | $ 13
Consumer Banking | Retail banking |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Number of Contracts | Contract | 1 | 8
Total Loans | $ | $ 0 | $ 0
Commercial Banking |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Number of Contracts | Contract | 6 | 0
Total Loans | $ | $ 28 | $ 0
Commercial Banking | Commercial and industrial |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Number of Contracts | Contract | 6 | 0
Total Loans | $ | $ 28 | $ 0
Domestic credit card: | Credit Card |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Number of Contracts | Contract | 10,886 | 14,027
Total Loans | $ | $ 22 | $ 29
International card businesses: | Credit Card |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Number of Contracts | Contract | 17,857 | 16,706
Total Loans | $ | $ 26 | $ 28

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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=118936363&loc=SL6953682-111524 + Details
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- Definition Amount of financing receivable modified as troubled debt restructuring within previous 12 months, with subsequent payment default. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 34 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953682-111524 + Details
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