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Stock-Based Compensation Plans - Additional Information (Detail) - USD ($) shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Equity Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense	$ 8.0
Weighted average period to recognize expense	2 years
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense	$ 251.0
Weighted average period to recognize expense	2 years 6 months
Performance Based Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense	$ 50.0
Weighted average period to recognize expense	1 year 8 months 12 days
Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserve for issuance or grant (shares)	6.0
Discount allowed to employees on purchase of shares under ESPP plan	5.00%	5.00%	5.00%
1998 and 2001 Plan \| Equity Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)	4 years
1998 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserve for issuance or grant (shares)	33.0
2001 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserve for issuance or grant (shares)	54.6
2001 Plan \| Instruments Other Than Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserve for issuance or grant (shares)	10.7
Directors' Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserve for issuance or grant (shares)	1.7
Award vesting period (in years)	1 year
Minimum \| Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employee subscription rate as a percentage of compensation	1.00%
Minimum \| 1998 and 2001 Plan \| Equity Option \| Employees at or Near Retirement Eligibility
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)	1 year
Minimum \| 1998 and 2001 Plan \| Performance Based Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)	3 years
Maximum \| Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employee subscription rate as a percentage of compensation	10.00%
Maximum \| 1998 and 2001 Plan \| Equity Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expiration period	10 years
Maximum \| 1998 and 2001 Plan \| Equity Option \| Employees at or Near Retirement Eligibility
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)	4 years
Maximum \| 1998 and 2001 Plan \| Performance Based Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)	4 years