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Benefit Plans (Narrative) (Detail) - USD ($) $ in Millions	12 Months Ended
Benefit Plans (Narrative) (Detail) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Pension and 401k expense	$ 2	$ 2	$ 3
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	17,750,000
Shares issued under Omnibus Plan in connection with stock options, count	1
Shares/units available for future grants	1,370,920
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	$ 5	6
Share-based compensation expense (benefit)	7	18	12
Tax charge related to share-based compensation	0	0	$ 0
Unrecognized compensation cost	$ 2
Expected to be recognized as expense over a weighted average period, years	1 year 10 months 13 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	71,193	255,340	216,460
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