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Stock-Based Compensation - Performance Stock Units (Details) - Long-Term Incentive Plans - Performance Shares - Common Shares - USD ($) $ / shares in Units, $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Stock based compensation, Nonvested shares rollforward, number of shares |  |  |
Nonvested stock units, beginning of period - Number of shares (in shares) | 1,457,000 |  |
Granted number of shares (in shares) | 409,000 |  |
Vested number of shares (in shares) | (263,000) |  |
Change in units based on approved performance factors number of shares | 114,000 |  |
Forfeited number of shares (in shares) | (109,000) |  |
Nonvested stock units, end of period - Number of shares (in shares) | 1,608,000 | 1,457,000 |
Stock based compensation, Nonvested shares weighted average grant date fair value |  |  |
Nonvested stock units - beginning of period weighted average grant date fair value (USD per share) | $ 27.37 |  |
Granted weighted average grant date fair value (USD per share) | 36.59 | $ 21.26 | $ 31.35
Vested weighted average grant date fair value (USD per share) | 20.06 |  |
Change in units based on approved performance factors weighted average grant date fair value | 23.06 |  |
Forfeited weighted average grant date fair value (USD per share) | 21.35 |  |
Nonvested stock units - end of period weighted average grant date fair value (USD per share) | $ 31.91 | $ 27.37 |
Shares issued and granted under stock compensation plans |  |  |
Fair value of vested stock units | $ 9 | $ 7 | $ 6
Award vesting period | 3 years |  |
2023 Modifications |  |  |
Shares issued and granted under stock compensation plans |  |  |
Incremental expense of award modification | $ 10 | $ 4 |
2024 Modifications |  |  |
Shares issued and granted under stock compensation plans |  |  |
Incremental expense of award modification | $ 6 |  |
2022 Grants |  |  |
Shares issued and granted under stock compensation plans |  |  |
Performance period | 3 years |  |
2023 Grants |  |  |
Shares issued and granted under stock compensation plans |  |  |
Performance period | 1 year |  |
2024 Grants |  |  |
Shares issued and granted under stock compensation plans |  |  |
Performance period | 1 year |  |
Chief Executive Officer |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Performance share awards target | 100.00% |  |
Minimum | 2022 Grants |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Performance share awards target | 75.00% |  |
Minimum | 2023 Grants |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Performance share awards target | 0.00% |  |
Minimum | 2024 Grants |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Performance share awards target | 0.00% |  |
Maximum | 2022 Grants |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Performance share awards target | 200.00% |  |
Maximum | 2023 Grants |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Performance share awards target | 150.00% |  |
Maximum | 2024 Grants |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Performance share awards target | 175.00% |  |

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- Definition The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(03) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 + Details
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- Definition The weighted average fair value at grant date for nonvested equity-based awards issued 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). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(01) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 + Details
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