Stock Compensation Plans Compensation and Unrecognized Compensation Expense (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Compensation expense
Total stock-based compensation expense	$ 23	$ 34	$ 36
Tax benefits recognized for stock-based compensation	7	10	9
Stock Awards
Compensation expense
Realized tax benefits from issuance of stock in settlement of RPSRs and RSRs	6	$ 7	$ 8
Restricted stock rights
Unrecognized compensation expense
Unrecognized compensation expense associated with stock awards	$ 16
Weighted average period of recognition of unrecognized compensation expense	1 year 1 month 6 days
Restricted performance stock rights
Unrecognized compensation expense
Unrecognized compensation expense associated with stock awards	$ 29
Weighted average period of recognition of unrecognized compensation expense	1 year

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Disclosure of the aggregate tax benefit realized from the issuance of stock and settlement of RPSRs and RSRs.

+ References

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-Publisher FASB
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
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-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
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- References

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (i)
-Publisher FASB
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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (i)
-Publisher FASB
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- Definition

Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-SubTopic 10
-Name Accounting Standards Codification
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