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Variable Interest Entities and Securitizations - Additional Information (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020
Variable Interest Entity [Line Items] |  |
Amortization method qualified affordable housing investments, amortization | $ 633 | $ 556
Affordable housing tax credits | 644 | 607
Amortization method qualified affordable housing investments | 4,700 | 4,500
Qualified affordable housing investments, commitment | 1,700 | 1,500
Carrying Amount of Assets | 432,381 | 421,602
VIE, reporting entity involvement, maximum loss exposure | 5,157 | 5,038
Unconsolidated |  |
Variable Interest Entity [Line Items] |  |
Carrying Amount of Assets | 5,157 | 5,038
Consolidated |  |
Variable Interest Entity [Line Items] |  |
Carrying Amount of Assets | 26,458 | 26,619
Affordable housing entities |  |
Variable Interest Entity [Line Items] |  |
VIE, reporting entity involvement, maximum loss exposure | 4,774 | 4,602
Affordable housing entities | Unconsolidated |  |
Variable Interest Entity [Line Items] |  |
Total assets of the unconsolidated VIE investment funds | 11,900 | 11,000
Carrying Amount of Assets | 4,774 | 4,602
Affordable housing entities | Consolidated |  |
Variable Interest Entity [Line Items] |  |
Carrying Amount of Assets | 263 | 242
Entities that provide capital to low-income and rural communities |  |
Variable Interest Entity [Line Items] |  |
VIE, reporting entity involvement, maximum loss exposure | 0 | 0
Entities that provide capital to low-income and rural communities | Unconsolidated |  |
Variable Interest Entity [Line Items] |  |
Carrying Amount of Assets | 0 | 0
Entities that provide capital to low-income and rural communities | Consolidated |  |
Variable Interest Entity [Line Items] |  |
Carrying Amount of Assets | 2,074 | 1,951
Other |  |
Variable Interest Entity [Line Items] |  |
VIE, reporting entity involvement, maximum loss exposure | 383 | 436
Other | Unconsolidated |  |
Variable Interest Entity [Line Items] |  |
Carrying Amount of Assets | 383 | 436
Other | Consolidated |  |
Variable Interest Entity [Line Items] |  |
Carrying Amount of Assets | $ 0 | $ 0

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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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