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Variable Interest Entities and Securitizations - Additional Information (Detail) - USD ($) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2020 | Mar. 31, 2019 | Dec. 31, 2019
Variable Interest Entity [Line Items] |  |  |
Amortization method qualified affordable housing investments, amortization | $ 139 | $ 143 |
Affordable housing tax credits | 155 | $ 171 |
Amortization method qualified affordable housing investments | 4,400 |  | $ 4,400
Qualified affordable housing investments, commitment | 1,400 |  | 1,500
Carrying Amount of Assets | 396,878 |  | 390,365
VIE, reporting entity involvement, maximum loss exposure | 5,410 |  | 5,413
Affordable housing entities |  |  |
Variable Interest Entity [Line Items] |  |  |
VIE, reporting entity involvement, maximum loss exposure | 4,594 |  | 4,559
Entities that provide capital to low-income and rural communities |  |  |
Variable Interest Entity [Line Items] |  |  |
VIE, reporting entity involvement, maximum loss exposure | 0 |  | 0
Other |  |  |
Variable Interest Entity [Line Items] |  |  |
VIE, reporting entity involvement, maximum loss exposure | 486 |  | 502
Unconsolidated |  |  |
Variable Interest Entity [Line Items] |  |  |
Carrying Amount of Assets | 5,139 |  | 5,127
Unconsolidated | Affordable housing entities |  |  |
Variable Interest Entity [Line Items] |  |  |
Total assets of the unconsolidated VIE investment funds | 10,800 |  | 10,900
Carrying Amount of Assets | 4,594 |  | 4,559
Unconsolidated | Entities that provide capital to low-income and rural communities |  |  |
Variable Interest Entity [Line Items] |  |  |
Carrying Amount of Assets | 0 |  | 0
Unconsolidated | Other |  |  |
Variable Interest Entity [Line Items] |  |  |
Carrying Amount of Assets | 486 |  | 502
Consolidated |  |  |
Variable Interest Entity [Line Items] |  |  |
Carrying Amount of Assets | 32,835 |  | 35,519
Consolidated | Affordable housing entities |  |  |
Variable Interest Entity [Line Items] |  |  |
Carrying Amount of Assets | 246 |  | 236
Consolidated | Entities that provide capital to low-income and rural communities |  |  |
Variable Interest Entity [Line Items] |  |  |
Carrying Amount of Assets | 1,967 |  | 1,889
Consolidated | Other |  |  |
Variable Interest Entity [Line Items] |  |  |
Carrying Amount of Assets | $ 0 |  | $ 0

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- Definition Variable Interest Entity, Nonconsolidated, Total Assets + References No definition available. + Details
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- Definition Amount of affordable housing tax credits and other tax benefits recognized. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 740 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=116633289&loc=SL49122993-202985 + Details
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- Definition Amount of investment in qualified affordable housing projects. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 740 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=116633289&loc=SL49122993-202985 + Details
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- Definition Amount of amortization expense of investment in qualified affordable housing projects. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 740 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=116633289&loc=SL49122993-202985 + Details
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- Definition Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. + References Reference 1: 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(11)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 22 -URI http://asc.fasb.org/extlink&oid=115929826&loc=d3e8736-108599 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(12)) -URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910 + Details
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- Definition Amount of commitment or contingent commitments to qualified affordable housing project investments. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 740 -Section 50 -Paragraph 2 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=116633289&loc=SL49122993-202985 + Details
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- Definition The reporting entity's maximum amount of exposure to loss as a result of its involvement with the Variable Interest Entity (VIE). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=118582676&loc=d3e5747-111685 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 4 -Subparagraph b -URI http://asc.fasb.org/extlink&oid=118582676&loc=d3e5728-111685 + Details
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