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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Stock Plans (Narrative) (Details) - USD ($) $ in Millions		6 Months Ended		12 Months Ended
Stock Plans (Narrative) (Details) - USD ($) $ in Millions	Feb. 28, 2025	Jun. 30, 2025	Jun. 30, 2024	Dec. 31, 2024	May 15, 2024
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized for grant under the plans (in shares)		9,916,334
2024 Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized for grant under the plans (in shares)		1,151,334			8,765,000
Shares available for grant under the plan (in shares)		8,336,901
PSUs 2022 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance metric percent	133.70%
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		3 years
Remaining unrecognized compensation cost associated with unvested restricted stock awards		$ 49
Weighted average period over which unvested restricted stock awards unrecognized compensation cost is expected to be recognized (in years)		2 years
Cash compensation		$ 16	$ 18
Restricted Stock [Member] \| 2024 Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock granted (in shares)		859,000
Performance Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Measurement period		3 years
Conversion of stock, ratio		1
Compensation expense		$ 12	18
Performance Stock [Member] \| 2024 Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock granted (in shares)		625,000
Performance Stock [Member] \| PSUs 2024 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance metric percent		33.30%
Performance Stock [Member] \| PSUs 2025 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance metric percent		50.00%
Performance Stock [Member] \| PSUs 2022 And 2023 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance metric percent		33.30%
Performance-Based Restricted Stock [Member] \| Chief Financial Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock granted (in shares)				501,000
Minimum [Member] \| Performance Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Payout range, percent of target units		0.00%
Maximum [Member] \| Restricted Stock [Member] \| Board of Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense		$ 1	$ 1
Maximum [Member] \| Performance Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Payout range, percent of target units		200.00%