Loans and leases receivable.

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Loans and leases weighted-average remaining term

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Percentage of loans in the process of foreclosure, serviced by other entities, classified as government guaranteed.

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- Definition

Residential mortgage loans secured by residential real estate in process of foreclosure.

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- Definition

Amount, before allowance for credit loss, of accrued interest on financing receivable.

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Amortized cost, before allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement and net investment in lease.

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Amortized cost, after allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement and net investment in lease.

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Carrying amount as of the balance sheet date of other real estate and foreclosed assets. Other real estate may include real estate investments, real estate loans that qualify as investments in real estate, and premises that are no longer used in operations may also be included in real estate owned. Foreclosed assets include all assets obtained in full or partial satisfaction of a debt arrangement through foreclosure proceedings.

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Loans and allowance for loan losses - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024	Dec. 31, 2024
Loans And Leases Receivable [Line Items]
Amount of foreclosed residential real estate property held	$ 30		$ 30		$ 35
Loans secured by residential real estate that were in the process of foreclosure	$ 194		$ 194		173
Percentage loans in the process of foreclosure, serviced by other entities, classified as government guaranteed	46.00%		46.00%
Financing receivable, accrued interest, before allowance for credit loss	$ 617		$ 617		628
Commercial and industrial
Loans And Leases Receivable [Line Items]
Weighted-average remaining term	7 months 6 days	8 months 12 days	9 months 18 days	9 months 18 days
Commercial and industrial \| Asset Pledged as Collateral without Right
Loans And Leases Receivable [Line Items]
Financing receivable, before allowance for credit loss	$ 20,900		$ 20,900
Commercial and industrial \| Asset Pledged as Collateral without Right \| FHLBs Facility
Loans And Leases Receivable [Line Items]
Pledged financial instruments					20,700
Commercial Real Estate
Loans And Leases Receivable [Line Items]
Weighted-average remaining term			9 months 18 days
Commercial Real Estate \| Asset Pledged as Collateral without Right
Loans And Leases Receivable [Line Items]
Financing receivable, before allowance for credit loss	$ 13,600		$ 13,600
Commercial Real Estate \| Asset Pledged as Collateral without Right \| FHLBs Facility
Loans And Leases Receivable [Line Items]
Pledged financial instruments					14,600
Residential Real Estate
Loans And Leases Receivable [Line Items]
Weighted-average remaining term	9 years 2 months 12 days	8 years 10 months 24 days	9 years 8 months 12 days	10 years 2 months 12 days
Residential Real Estate \| Asset Pledged as Collateral without Right
Loans And Leases Receivable [Line Items]
Financing receivable, before allowance for credit loss	$ 19,000		$ 19,000
Residential Real Estate \| Asset Pledged as Collateral without Right \| FHLBs Facility
Loans And Leases Receivable [Line Items]
Pledged financial instruments					18,600
Residential builder and developer
Loans And Leases Receivable [Line Items]
Weighted-average remaining term		7 months 6 days		9 months 18 days
Home equity lines and loans \| Consumer \| Asset Pledged as Collateral without Right
Loans And Leases Receivable [Line Items]
Financing receivable, before allowance for credit loss	2,800		2,800
Home equity lines and loans \| Consumer \| Asset Pledged as Collateral without Right \| FHLBs Facility
Loans And Leases Receivable [Line Items]
Pledged financial instruments					2,700
Other \| Consumer \| Asset Pledged as Collateral without Right
Loans And Leases Receivable [Line Items]
Financing receivable, before allowance for credit loss	$ 13,200		$ 13,200
Other \| Consumer \| Asset Pledged as Collateral without Right \| FHLBs Facility
Loans And Leases Receivable [Line Items]
Pledged financial instruments					$ 13,100