Loans and Leases - Schedule of Performance of Loans that have been Modified in the Last 12 Months (Details) - USD ($) $ in Millions	Jun. 30, 2026	Jun. 30, 2025
Financing Receivable, Troubled Debt Restructuring [Line Items]
Non-Accruing	$ 60	$ 176
Total	324	559
Current
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loans	257	375
30-89 Days Past Due
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loans	7	8
90+ Days Past Due
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loans	0	0
Commercial \| Commercial and industrial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Non-Accruing	19	27
Total	178	162
Commercial \| Commercial and industrial \| Current
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loans	152	127
Commercial \| Commercial and industrial \| 30-89 Days Past Due
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loans	7	8
Commercial \| Commercial and industrial \| 90+ Days Past Due
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loans	0	0
Commercial \| Commercial real estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Non-Accruing	38	148
Total	142	395
Commercial \| Commercial real estate \| Current
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loans	104	247
Commercial \| Commercial real estate \| 30-89 Days Past Due
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loans	0	0
Commercial \| Commercial real estate \| 90+ Days Past Due
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loans	0	0
Consumer \| Consumer Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Non-Accruing	3	1
Total	4	2
Consumer \| Consumer Real Estate \| Current
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loans	1	1
Consumer \| Consumer Real Estate \| 30-89 Days Past Due
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loans	0	0
Consumer \| Consumer Real Estate \| 90+ Days Past Due
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loans	$ 0	$ 0

Financing Receivable, Excluding Accrued Interest, Modified, After 12 Months, Including Nonaccruring

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- Definition

Financing Receivable, Excluding Accrued Interest, Non-Accruing, Modified, During Past 12 Months

+ References

No definition available.

+ Details

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- Definition

Amortized cost excluding accrued interest, of financing receivable 12 months after modification for debtor experiencing financial difficulty.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
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-Publisher FASB
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 310
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-Section 55
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-Publisher FASB
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