Loans - Summary of Nonaccrual Loans (Detail) - USD ($) $ in Millions	Jun. 30, 2026	Dec. 31, 2025
Financing Receivable, Impaired [Line Items]
Nonaccrual loans	$ 3,486	$ 3,387
Total divided by gross loans at amortized cost	1.50%	1.60%
Nonaccrual loans allowance for loans losses divided by total	62.80%	63.40%
Past due
Financing Receivable, Impaired [Line Items]
Nonaccrual loans	$ 813	$ 756
Corporate
Financing Receivable, Impaired [Line Items]
Nonaccrual loans	1,784	2,065
Commercial real estate
Financing Receivable, Impaired [Line Items]
Nonaccrual loans	1,186	1,079
Residential real estate
Financing Receivable, Impaired [Line Items]
Nonaccrual loans	72	85
Other collateralized
Financing Receivable, Impaired [Line Items]
Nonaccrual loans	424	121
Other
Financing Receivable, Impaired [Line Items]
Nonaccrual loans	$ 20	$ 37

Amortized cost of financing receivable on nonaccrual status. Excludes net investment in lease.

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