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Stock Options, Restricted Stock, and Dividend Reinvestment Plans - Narrative (Details) - USD ($) | 12 Months Ended
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Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Options granted (in shares) | 4,558,402 |  |  |
Number of outstanding awards with stock price performance conditions (in shares) | 1 |  |  |
Award vesting period | 3 years |  |  |
Percent of performance condition achieved | 100.00% |  |  |
Value of annual equity awards to non employee directors | $ 122,000 | $ 122,000 |  |
Total intrinsic value of options exercised | $ 4,000,000 | 17,000,000 | $ 12,000,000 |
Stock options granted or converted (in shares) | 0 |  | 155,124 |
Grants in period, weighted average grant date fair value (in dollars per share) |  |  | $ 3.39 |
Stock-based compensation expense | $ 36,000,000 | 75,000,000 | $ 43,000,000 |
Total income tax benefits recognized | $ 8,000,000 | 18,000,000 | 10,000,000 |
Stock Appreciation Rights (SARs) |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Options granted (in shares) | 0 |  |  |
Nonvested Restricted Stock Plans |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Employee service share-based compensation, nonvested awards, compensation cost not yet recognized | $ 78,000,000 |  |  |
Employee service share-based compensation, nonvested awards, compensation cost not yet recognized, period for recognition | 2 years |  |  |
Total grant date fair value of shares vested | $ 32,000,000 | $ 29,000,000 | $ 36,000,000 |
Employee Stock Option |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Award vesting period | 7 years |  |  |
Employee service share-based compensation, nonvested awards, compensation cost not yet recognized, period for recognition | 2 months 12 days |  |  |
Employee Stock Option | Tranche 1 |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Expiration period | 7 years |  |  |
Employee Stock Option | Tranche 2 |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Expiration period | 10 years |  |  |
Employee Stock Option | Tranche 3 |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Expiration period | 10 years |  |  |
Employee Stock Option | Tranche 4 |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Expiration period | 20 years |  |  |
Phantom Stock Awards |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Award vesting period | 5 years |  |  |
Shares outstanding (in shares) | 199,114 |  |  |
Equity Compensation Plans |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Number of shares available for new awards (in shares) | 4,965,419 |  |  |
Performance Condition Awards |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Duration of performance evaluation | 3 years | 3 years | 3 years |
Performance Condition Awards | PSUs Granted Between 2014 And 2020 |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Post vest holding period | 2 years | 2 years |  |
Percent of performance condition achieved | 187.50% | 187.50% | 133.30% |
Market Condition Award | Minimum |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Award vesting period |  |  |  | 7 years
Dividend Reinvestment Plan | Minimum |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Quarterly value of shares available for purchase under dividend reinvestment and stock purchase plan | $ 25 |  |  |
Dividend Reinvestment Plan | Maximum |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Quarterly value of shares available for purchase under dividend reinvestment and stock purchase plan | $ 10,000 |  |  |

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