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Allowance for Credit Losses and Reserve for Unfunded Lending Commitments - Allowance for Loan and Lease Losses and Reserve for Unfunded Lending Commitments Activity (Detail) - USD ($) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2020 | Mar. 31, 2019 | Jan. 01, 2020
Allowance for Loan and Lease Losses [Roll Forward] |  |  |
Balance at the beginning of the period | $ 7,208 |  |
Allowance for Credit Losses [Roll Forward] |  |  |
Balance at the end of the period | 14,073 |  |
Allowance for credit losses |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |
Balance at the beginning of the period | 7,208 | $ 7,220 |
Charge-offs |  | (2,273) |
Recoveries |  | 674 |
Net charge-offs |  | (1,599) |
Provision for loan and lease losses |  | 1,684 |
Allowance build for loan and lease losses |  | 85 |
Other changes |  | 8 |
Balance at the end of the period |  | 7,313 |
Allowance for Credit Losses [Roll Forward] |  |  |
Finance charge and fee reserve reclassification |  |  | $ 462
Charge-offs | (2,457) |  |
Recoveries | 666 |  |
Net charge-offs | (1,791) |  |
Provision for credit losses | 5,367 |  |
Allowance build for credit losses | 3,576 |  |
Other changes | (18) |  |
Balance at the end of the period | 14,073 |  |
Allowance for credit losses | Adjustment amount |  |  |
Allowance for Credit Losses [Roll Forward] |  |  |
Balance at the beginning of the period | 2,845 |  |
Finance charge and fee reserve reclassification |  |  | 462
Allowance for credit losses | Adjusted balance |  |  |
Allowance for Credit Losses [Roll Forward] |  |  |
Balance at the beginning of the period | 10,515 |  |
Reserve for unfunded lending commitments |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |
Balance at the beginning of the period | 135 |  |
Provision for loan and lease losses |  | 9 |
Balance at the end of the period |  | 131 |
Allowance for Credit Losses [Roll Forward] |  |  |
Provision for credit losses | 51 |  |
Balance at the end of the period | 223 |  |
Reserve for unfunded lending commitments | Adjustment amount |  |  |
Allowance for Credit Losses [Roll Forward] |  |  |
Balance at the beginning of the period | 37 |  |
Reserve for unfunded lending commitments | Adjusted balance |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |
Balance at the beginning of the period |  | 122 |
Allowance for Credit Losses [Roll Forward] |  |  |
Balance at the beginning of the period | 172 |  |
Combined allowance and reserve |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |
Balance at the end of the period |  | 7,444 |
Allowance for Credit Losses [Roll Forward] |  |  |
Balance at the end of the period | 14,296 |  |
Credit Card |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |
Balance at the beginning of the period | 5,395 | 5,535 |
Charge-offs |  | (1,782) |
Recoveries |  | 418 |
Net charge-offs |  | (1,364) |
Provision for loan and lease losses |  | 1,389 |
Allowance build for loan and lease losses |  | 25 |
Other changes |  | 8 |
Balance at the end of the period |  | 5,568 |
Allowance for Credit Losses [Roll Forward] |  |  |
Charge-offs | (1,849) |  |
Recoveries | 413 |  |
Net charge-offs | (1,436) |  |
Provision for credit losses | 3,702 |  |
Allowance build for credit losses | 2,266 |  |
Other changes | (18) |  |
Balance at the end of the period | 10,346 |  |
Credit Card | Adjustment amount |  |  |
Allowance for Credit Losses [Roll Forward] |  |  |
Balance at the beginning of the period | 2,241 |  |
Finance charge and fee reserve reclassification |  |  | 462
Credit Card | Adjusted balance |  |  |
Allowance for Credit Losses [Roll Forward] |  |  |
Balance at the beginning of the period | 8,098 |  |
Credit Card | Reserve for unfunded lending commitments |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |
Balance at the beginning of the period | 0 |  |
Provision for loan and lease losses |  | 0 |
Balance at the end of the period |  | 0 |
Allowance for Credit Losses [Roll Forward] |  |  |
Provision for credit losses | 0 |  |
Balance at the end of the period | 0 |  |
Credit Card | Reserve for unfunded lending commitments | Adjustment amount |  |  |
Allowance for Credit Losses [Roll Forward] |  |  |
Balance at the beginning of the period | 0 |  |
Credit Card | Reserve for unfunded lending commitments | Adjusted balance |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |
Balance at the beginning of the period |  | 0 |
Allowance for Credit Losses [Roll Forward] |  |  |
Balance at the beginning of the period | 0 |  |
Credit Card | Combined allowance and reserve |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |
Balance at the end of the period |  | 5,568 |
Allowance for Credit Losses [Roll Forward] |  |  |
Balance at the end of the period | 10,346 |  |
Consumer Banking |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |
Balance at the beginning of the period | 1,038 | 1,048 |
Charge-offs |  | (471) |
Recoveries |  | 250 |
Net charge-offs |  | (221) |
Provision for loan and lease losses |  | 235 |
Allowance build for loan and lease losses |  | 14 |
Other changes |  | 0 |
Balance at the end of the period |  | 1,062 |
Allowance for Credit Losses [Roll Forward] |  |  |
Charge-offs | (496) |  |
Recoveries | 250 |  |
Net charge-offs | (246) |  |
Provision for credit losses | 860 |  |
Allowance build for credit losses | 614 |  |
Other changes | 0 |  |
Balance at the end of the period | 2,154 |  |
Consumer Banking | Adjustment amount |  |  |
Allowance for Credit Losses [Roll Forward] |  |  |
Balance at the beginning of the period | 502 |  |
Finance charge and fee reserve reclassification |  |  | 0
Consumer Banking | Adjusted balance |  |  |
Allowance for Credit Losses [Roll Forward] |  |  |
Balance at the beginning of the period | 1,540 |  |
Consumer Banking | Reserve for unfunded lending commitments |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |
Balance at the beginning of the period | 5 |  |
Provision for loan and lease losses |  | 0 |
Balance at the end of the period |  | 4 |
Allowance for Credit Losses [Roll Forward] |  |  |
Provision for credit losses | 0 |  |
Balance at the end of the period | 0 |  |
Consumer Banking | Reserve for unfunded lending commitments | Adjustment amount |  |  |
Allowance for Credit Losses [Roll Forward] |  |  |
Balance at the beginning of the period | (5) |  |
Consumer Banking | Reserve for unfunded lending commitments | Adjusted balance |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |
Balance at the beginning of the period |  | 4 |
Allowance for Credit Losses [Roll Forward] |  |  |
Balance at the beginning of the period | 0 |  |
Consumer Banking | Combined allowance and reserve |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |
Balance at the end of the period |  | 1,066 |
Allowance for Credit Losses [Roll Forward] |  |  |
Balance at the end of the period | 2,154 |  |
Commercial Banking |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |
Balance at the beginning of the period | 775 | 637 |
Charge-offs |  | (20) |
Recoveries |  | 6 |
Net charge-offs |  | (14) |
Provision for loan and lease losses |  | 60 |
Allowance build for loan and lease losses |  | 46 |
Other changes |  | 0 |
Balance at the end of the period |  | 683 |
Allowance for Credit Losses [Roll Forward] |  |  |
Charge-offs | (112) |  |
Recoveries | 3 |  |
Net charge-offs | (109) |  |
Provision for credit losses | 805 |  |
Allowance build for credit losses | 696 |  |
Other changes | 0 |  |
Balance at the end of the period | 1,573 |  |
Commercial Banking | Adjustment amount |  |  |
Allowance for Credit Losses [Roll Forward] |  |  |
Balance at the beginning of the period | 102 |  |
Finance charge and fee reserve reclassification |  |  | $ 0
Commercial Banking | Adjusted balance |  |  |
Allowance for Credit Losses [Roll Forward] |  |  |
Balance at the beginning of the period | 877 |  |
Commercial Banking | Reserve for unfunded lending commitments |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |
Balance at the beginning of the period | 130 |  |
Provision for loan and lease losses |  | 9 |
Balance at the end of the period |  | 127 |
Allowance for Credit Losses [Roll Forward] |  |  |
Provision for credit losses | 51 |  |
Balance at the end of the period | 223 |  |
Commercial Banking | Reserve for unfunded lending commitments | Adjustment amount |  |  |
Allowance for Credit Losses [Roll Forward] |  |  |
Balance at the beginning of the period | 42 |  |
Commercial Banking | Reserve for unfunded lending commitments | Adjusted balance |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |
Balance at the beginning of the period |  | 118 |
Allowance for Credit Losses [Roll Forward] |  |  |
Balance at the beginning of the period | 172 |  |
Commercial Banking | Combined allowance and reserve |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |
Balance at the end of the period |  | $ 810 |
Allowance for Credit Losses [Roll Forward] |  |  |
Balance at the end of the period | $ 1,796 |  |

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- Definition Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c)(4) -URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953423-111524 + Details
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- Definition Amount of other addition (reduction) in allowance reserve for credit loss. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5212-111524 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.7(d)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
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- Definition Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c)(3) -URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953423-111524 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.7(d)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
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- Definition Amount of increase in allowance for credit loss on financing receivable purchased with credit deterioration. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919249-210447 + Details
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- Definition Amount, after recovery, of writeoff of financing receivable, charged against allowance for credit loss. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919249-210447 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 55 -Paragraph 79 -URI http://asc.fasb.org/extlink&oid=118955255&loc=SL82922352-210448 + Details
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- Definition Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953423-111524 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=118955202&loc=SL82895884-210446 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919249-210447 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(7)(d)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919249-210447 + Details
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