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Period of increase in weighted-average maturity of financing receivable modified for debtor experiencing financial difficulty, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Loans - Summary of the Financial Effect of Loan Payment Modifications (Details) - Commercial loans - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Commercial mortgages \| Weighted-Average Interest Rate Reduction
Financing Receivable, Modified [Line Items]
Weighted-Average Interest Rate Reduction	0.00%		0.00%
Commercial mortgages \| Principal Forgiven
Financing Receivable, Modified [Line Items]
Principal Forgiven (in millions)	$ 0		$ 0
Commercial mortgages \| Weighted-Average Term Extension / Payment Deferral (in years)
Financing Receivable, Modified [Line Items]
Weighted-Average Term Extension / Payment Deferral (in years)	5 years 6 months		4 years 8 months 12 days
Business and corporate banking \| Weighted-Average Interest Rate Reduction
Financing Receivable, Modified [Line Items]
Weighted-Average Interest Rate Reduction	3.10%	0.20%	3.10%	0.20%
Business and corporate banking \| Principal Forgiven
Financing Receivable, Modified [Line Items]
Principal Forgiven (in millions)	$ 0	$ 0	$ 0	$ 0
Business and corporate banking \| Weighted-Average Term Extension / Payment Deferral (in years)
Financing Receivable, Modified [Line Items]
Weighted-Average Term Extension / Payment Deferral (in years)	2 years 9 months 18 days	1 year	2 years 4 months 24 days	1 year