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Stock Incentive Plans and Stock Purchase Plans - Additional Information (Detail) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 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 | 820,101 |  |
Common stock, aggregate shares authorized | 200,000,000 | 200,000,000 |
Stock-based compensation expense | $ 12,300,000 | $ 14,400,000 | $ 19,000,000
Aggregate fair value of restricted and deferred stocks vested | $ 9,600 | $ 19,100,000 | $ 25,100,000
Weighted average grant-date fair value of restricted and deferred stock awards granted | $ 15.25 | $ 22.64 | $ 25.17
Stock Option, Share Based Compensation Cost Not Yet Recognized Period For Recognition | $ 0 |  |
Employee Stock Option |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Award vesting period | 3 years |  |
Aggregate number Shares issued under Stock Purchase Plans | 400,000 |  |
Employee Stock Option | 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 4 months 24 days |  |
Unrecognized compensation expense related to non-vested restricted shares | $ 8,700 |  |
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] | Employee Stock Option |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Shares available for future grants and awards under Stock Incentive Plans | 9,000 |  |
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 |  |
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 | 0 |  |
Common stock, reserved for issuance | 2,100,000 |  |
1996 Non-Qualified Employee Stock Purchase Plan and 2015 Non-Qualified Stock Purchase Plan [Member] | Employee Stock Option |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Common stock, reserved for issuance | 61,000 |  |

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