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Variable Interest Entities and Asset Securitizations - Additional Information (Detail) - USD ($) | 3 Months Ended | 9 Months Ended |  |  |
--- | --- | --- | --- | --- | ---
Sep. 30, 2024 | Sep. 30, 2023 | Sep. 30, 2024 | Sep. 30, 2023 | Aug. 31, 2024 | Mar. 31, 2024 | Dec. 31, 2023
Loss on securitization of assets |  |  | $ 0 |  |  |  |
Long-term borrowings | $ 11,583,000,000 |  | 11,583,000,000 |  |  |  | $ 8,201,000,000
Loans | 133,716,000,000 |  | 133,716,000,000 |  |  |  | 131,939,000,000
Other assets for its "investment" in the common securities recognized by the company of various trusts | 22,000,000 |  | 22,000,000 |  |  |  | 22,000,000
Total assets of partnerships in which the company invested | 211,785,000,000 |  | 211,785,000,000 |  |  |  | 208,264,000,000
Secured Debt |  |  |  |  |  |  |
Long-term debt term (in years) |  |  |  |  |  | 2 years |
Loans and leases average rate |  |  |  |  |  | 5.29% |
Secured Debt | Automobile |  |  |  |  |  |  |
Financing receivable, accrued interest, before allowance for credit loss | 418,000,000 |  | 418,000,000 |  |  | $ 526,000,000 |
Long-term debt term (in years) |  |  |  |  |  | 2 years |
Loans and leases average rate |  |  |  |  |  | 5.29% |
Secured Debt | Equipment Finance Loans And Leases |  |  |  |  |  |  |
Financing receivable, accrued interest, before allowance for credit loss | 742,000,000 |  | 742,000,000 |  | $ 790,000,000 |  |
Long-term debt term (in years) |  |  |  |  | 2 years |  |
Loans and leases average rate |  |  |  |  | 4.87% |  |
Secured Debt | Third Party Investors | Automobile |  |  |  |  |  |  |
Financing receivable, accrued interest, before allowance for credit loss |  |  |  |  |  | $ 511,000,000 |
Long-term borrowings | 406,000,000 |  | 406,000,000 |  |  |  |
Secured Debt | Third Party Investors | Equipment Finance Loans And Leases |  |  |  |  |  |  |
Financing receivable, accrued interest, before allowance for credit loss |  |  |  |  | $ 650,000,000 |  |
Long-term borrowings | 614,000,000 |  | 614,000,000 |  |  |  |
Secured Debt | M&T Bank | Automobile |  |  |  |  |  |  |
Financing receivable, accrued interest, before allowance for credit loss |  |  |  |  |  | $ 15,000,000 |
Secured Debt | M&T Bank | Equipment Finance Loans And Leases |  |  |  |  |  |  |
Financing receivable, accrued interest, before allowance for credit loss |  |  |  |  | $ 140,000,000 |  |
Variable Interest Entity Primary Beneficiary |  |  |  |  |  |  |
Total assets of partnerships in which the company invested | 10,000,000,000.0 |  | 10,000,000,000.0 |  |  |  | $ 9,800,000,000
Federal tax credits and other federal tax benefits recognized | 10,000,000 | $ 6,000,000 | 25,000,000 | $ 22,000,000 |  |  |
Investments amortized to income tax expense | 47,000,000 | 46,000,000 | 135,000,000 | 128,000,000 |  |  |
Maximum exposure to loss of investments in real estate partnerships | 2,100,000,000 |  | 2,100,000,000 |  |  |  |
Variable Interest Entity Primary Beneficiary | Renewable Energy |  |  |  |  |  |  |
Federal tax credits and other federal tax benefits recognized | 8,000,000 | 10,000,000 | 8,000,000 | 10,000,000 |  |  |
Investments amortized to income tax expense | $ 28,000,000 | $ 22,000,000 | $ 28,000,000 | $ 22,000,000 |  |  |

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