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v3.21.2

Variable Interest Entities (Narrative) (Detail) $ in Millions | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Mar. 31, 2021 | Mar. 31, 2020 | Jun. 30, 2021 USD ($) | Dec. 31, 2020 USD ($)
Variable Interest Entity [Line Items] |  |  |  |
Carrying amounts of assets |  |  | $ 5,252 | $ 5,751
Carrying amounts of liabilities |  |  | 5,275 | 5,602
Variable Interest Entity Primary Beneficiary [Member] |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |
Carrying amounts of assets |  |  | 218 | 830
Carrying amounts of liabilities |  |  | $ 450 | $ 623
Variable Interest Entity Primary Beneficiary [Member] | US Public Finance [Member] |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |
Number of variable interest entities deconsolidated |  | 7 |  |
Number of variable interest entities consolidated |  | 0 |  |
Variable Interest Entity Primary Beneficiary [Member] | Structured Finance And International Insurance [Member] |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |
Number of variable interest entities deconsolidated | 0 | 1 | 2 |
Variable Interest Entity Primary Beneficiary [Member] | Structured Finance And International Insurance [Member] | Recorded Due To Credit Losses In AOCI [Member] |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |
Net realized gains (losses) related to deconsolidation |  |  | $ (5) |

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