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Stock Incentive Plans and Stock Purchase Plans - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	May 12, 2021	May 11, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	841,196
Common stock, aggregate shares authorized	200,000,000	200,000,000
Stock-based compensation expense	$ 14,400,000	$ 19,000,000.0	$ 21,100,000
Aggregate fair value of restricted and deferred stocks vested	$ 19,100,000	$ 25,100,000	$ 59,300,000
Weighted average grant-date fair value of restricted and deferred stock awards granted	$ 22.64	$ 25.17	$ 23.54
Stock Option, Share Based Compensation Cost Not Yet Recognized Period For Recognition	$ 0
Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	3 years
Stock Option [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of options, maximum years	10 years
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	3 years
Restricted and Deferred Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense related to non-vested restricted stock, weighted-average period in years	1 year 6 months
Unrecognized compensation expense related to non-vested restricted shares	$ 10,700
1996 Non-Qualified Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares common stock reserved				9,900,000
2015 Non-Qualified Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of market value of common stock at which employees are permitted to purchase	90.00%
Amended and Restated 2008 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares common stock reserved				34,975,000	27,775,000
Amended and Restated 2008 Plan [Member] | Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for future grants and awards under Stock Incentive Plans	9,300,000
Amended and Restated 2008 Plan [Member] | Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	800,000
1996 Non-Qualified Employee Stock Purchase Plan and 2015 Non-Qualified Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of market value of common stock at which employees are permitted to purchase	85.00%
Aggregate number Shares issued under Stock Purchase Plans	300,000
Common stock, reserved for issuance	2,500,000
1996 Non-Qualified Employee Stock Purchase Plan and 2015 Non-Qualified Stock Purchase Plan [Member] | Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, reserved for issuance	61,000,000,000

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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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).

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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