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Benefit Plans (Narrative) (Detail) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] |  |  |
Pension and 401k expense | $ 2 | $ 3 | $ 4
Defined contribution pension [Member] |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] |  |  |
Percentage of company contribution of the employees annual compensation | 10.00% |  |
Vested after two years | 20.00% |  |
Vested after three years | 60.00% |  |
Vested after four years | 80.00% |  |
Vested after five years | 100.00% |  |
Qualified profit-sharing/401(k) [Member] |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] |  |  |
Contribution percentage of eligible employees compensation | 25.00% |  |
Vested after two years | 20.00% |  |
Vested after three years | 60.00% |  |
Vested after four years | 80.00% |  |
Vested after five years | 100.00% |  |
Contributions percentage of employer match | 5.00% |  |
Maximum [Member] | Defined contribution pension [Member] |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] |  |  |
Maximum annual compensation subject to pension | $ 2 |  |
Omnibus Plan [Member] |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] |  |  |
Shareholder approved increase in common stock reserved and available for issuance | 17,400,000 |  |
Shares issued under Omnibus Plan in connection with stock options, count | 1 |  |
Shares/units available for future grants | 1,760,032 |  |
Omnibus Plan [Member] | After May 1, 2012 Amendment [Member] |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] |  |  |
Shares issued under Omnibus Plan in connection with other than stock options, count | 1.28 |  |
Omnibus Plan [Member] | Prior To May 1, 2012 Amendment [Member] |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] |  |  |
Shares issued under Omnibus Plan in connection with other than stock options, count | 2 |  |
Restricted Stock [Member] |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] |  |  |
Stock issued during period, value, restricted stock award, gross | $ 6 | 6 |
Share-based compensation expense (benefit) | 18 | 12 | 12
Tax charge related to share-based compensation | 0 | $ 0 | $ 0
Unrecognized compensation cost | $ 4 |  |
Expected to be recognized as expense over a weighted average period, years | 1 year 3 months 21 days |  |
Accelerated compensation expense | $ 5 |  |
Restricted Stock [Member] | No Change in Fair Value of Awards [Member] |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] |  |  |
Additional compensation expense recognized | $ 0 |  |
Restricted Stock [Member] | Stock Price Targets [Member] |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] |  |  |
Restricted shares granted | 255,340 | 216,460 | 502,822
Restricted Stock [Member] | Minimum [Member] |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] |  |  |
Long-term incentive awards vesting period, years | 3 years |  |
Restricted Stock [Member] | Maximum [Member] |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] |  |  |
Long-term incentive awards vesting period, years | 7 years |  |

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