Stock Option Plan - Additional Information (Detail)					12 Months Ended
	May 13, 2022 USD ($) person $ / shares shares	May 07, 2021 USD ($) person $ / shares shares	Dec. 31, 2020 shares	Apr. 24, 2020 USD ($) person $ / shares shares	Dec. 31, 2023 USD ($) $ / shares shares	Dec. 31, 2022 USD ($) $ / shares	Dec. 31, 2021 USD ($) $ / shares	Dec. 31, 2004	Dec. 31, 2005 shares
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Deferred compensation (in shares) | shares			123,361		10,762
Exercise price of options (in usd per share) | $ / shares					$ 33.79	$ 47.90	$ 43.89
Intrinsic value of options exercised						$ 200,000	$ 400,000
Intrinsic value of options outstanding					$ 1,200,000	$ 0
Intrinsic value of options exercisable					$ 200,000
Closing price (in usd per share) | $ / shares					$ 39.27
Allocated share based compensation					$ 1,200,000
Future expense					$ 2,000,000
Weighted average remaining life of options exercisable					4 years
Weighted average remaining life of options outstanding					5 years 3 months 18 days
2019 Options
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Exercise price of options (in usd per share) | $ / shares				$ 43.89
Fair value stock option grant				$ 1,400,000
2020 Options
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Exercise price of options (in usd per share) | $ / shares		$ 47.90
Fair value stock option grant		$ 1,800,000
2021 Options
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Exercise price of options (in usd per share) | $ / shares	$ 33.79
Fair value stock option grant	$ 1,400,000
Common Stock
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Shares due to exercise of employee stock options and issuance of directors' deferred stock | shares					8,225
Officer | 2019 Options
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Number of individuals granted options | person				21
Options vested				25.00%
Fair value stock option grant				$ 1,200,000
Officer | 2020 Options
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Number of individuals granted options | person		19
Options vested		25.00%
Fair value stock option grant		$ 1,600,000
Officer | 2021 Options
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Number of individuals granted options | person	18
Options vested	25.00%
Fair value stock option grant	$ 1,200,000
Director | 2019 Options
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Number of individuals granted options | person				11
Fair value stock option grant				$ 173,800
Director | 2020 Options
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Number of individuals granted options | person		11
Fair value stock option grant		$ 229,350
Director | 2021 Options
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Number of individuals granted options | person	12
Fair value stock option grant	$ 195,900
Stock options
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Expiration period								10 years
Stock options | Amended 2004 Plan
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Authorized shares for a grant | shares									3,400,000
Stock options | 2019 Options
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Options granted to purchase stocks (in shares) | shares				250,500
Stock options | 2020 Options
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Options granted to purchase stocks (in shares) | shares		248,000
Stock options | 2021 Options
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Options granted to purchase stocks (in shares) | shares	253,500
Stock options | Officer
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Option vesting period								4 years
Stock options | Officer | 2019 Options
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Option vesting period				4 years
Stock options | Officer | 2020 Options
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Option vesting period		4 years			4 years
Stock options | Officer | 2021 Options
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Option vesting period	4 years				4 years
Incentive stock option | 2019 Options
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Options granted to purchase stocks (in shares) | shares				35,572
Incentive stock option | 2020 Options
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Options granted to purchase stocks (in shares) | shares		25,745
Incentive stock option | 2021 Options
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Options granted to purchase stocks (in shares) | shares	31,509
Nonqualified stock options | 2019 Options
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Options granted to purchase stocks (in shares) | shares				214,928
Nonqualified stock options | 2020 Options
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Options granted to purchase stocks (in shares) | shares		222,255
Nonqualified stock options | 2021 Options
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Options granted to purchase stocks (in shares) | shares	221,991