Defined Benefit Plan, Vesting Period

No definition available.

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- Definition

Amount of actuarial present value of benefits attributed to employee service rendered, excluding assumptions about future compensation level.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
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- Definition

Amount of administration expense of defined benefit plan which decreases plan assets. Excludes plan administration expense paid by employer.

+ References

No definition available.

+ Details

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- Definition

Amount of cost of providing special or contractual termination benefits payable from defined benefit plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-SubTopic 20
-Name Accounting Standards Codification
-Section 50
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-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

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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

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- Definition

Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

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Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 715
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- Definition

Amount of gain (loss) recognized in net periodic benefit (cost) credit from event reducing expected years of future service of present employees or eliminating accrual of defined benefits for some or all future services of present employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
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- Details

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Retirement and Benefit Plans - Narrative (Details) - Pension Plan $ in Millions	3 Months Ended	5 Months Ended	6 Months Ended
	Jun. 30, 2026 USD ($)	Jun. 30, 2026 USD ($)	Jun. 30, 2026 USD ($)
Defined Benefit Plan, Plan Assets, Category [Line Items]
Curtailment gain	$ 6		$ 6
Expense related to retirement termination benefit	0		$ 11
Acquired Comerica Plans
Defined Benefit Plan, Plan Assets, Category [Line Items]
Vesting period (years)			3 years
Nonqualified Plan \| Acquired Comerica Plans
Defined Benefit Plan, Plan Assets, Category [Line Items]
Accumulated benefit obligation	149	$ 149	$ 149
Qualified Plan
Defined Benefit Plan, Plan Assets, Category [Line Items]
Fees paid for accounting and administrative duties to Trustee		0
Qualified Plan \| Acquired Comerica Plans
Defined Benefit Plan, Plan Assets, Category [Line Items]
Accumulated benefit obligation	$ 1,557	$ 1,557	$ 1,557
Fixed Income Securities \| Qualified Plan \| Minimum
Defined Benefit Plan, Plan Assets, Category [Line Items]
Target allocations for plan investments	55.00%	55.00%	55.00%
Fixed Income Securities \| Qualified Plan \| Maximum
Defined Benefit Plan, Plan Assets, Category [Line Items]
Target allocations for plan investments	65.00%	65.00%	65.00%
Equity securities \| Qualified Plan \| Minimum
Defined Benefit Plan, Plan Assets, Category [Line Items]
Target allocations for plan investments	35.00%	35.00%	35.00%
Equity securities \| Qualified Plan \| Maximum
Defined Benefit Plan, Plan Assets, Category [Line Items]
Target allocations for plan investments	45.00%	45.00%	45.00%