Stock-based Employee Compensation, Stock Option Plans, and Deferred Compensation Plan for Directors - Narrative (Details) - USD ($)		3 Months Ended
Mar. 31, 2023	Mar. 31, 2023	Mar. 31, 2022
Schedule Of Share Based Compensation Arrangements By Share Based Payment Award Options [Line Items]
Deferred compensation (in shares)	116,306	2,347
Shares due to exercise of employee stock options and issuance of directors' deferred stock		699	8,007
Share-based payment arrangement, expense		$ 300,000
Future expense	$ 1,900,000	1,900,000
Exercised		$ 0	$ 43,548
Closing share price (in usd per share)	$ 39.00	$ 39.00
Share-based compensation arrangement by share-based payment award, options, grants since inception	1,800,000	1,800,000
Weighted average remaining contractual life of the Company's outstanding options		5 years 6 months
Weighted average remaining contractual life of the Company's exercisable options		4 years 6 months
Common Stock
Schedule Of Share Based Compensation Arrangements By Share Based Payment Award Options [Line Items]
Shares due to exercise of employee stock options and issuance of directors' deferred stock		6,865
Employee Stock Option
Schedule Of Share Based Compensation Arrangements By Share Based Payment Award Options [Line Items]
Expiration period		10 years
Employee Stock Option \| Officer
Schedule Of Share Based Compensation Arrangements By Share Based Payment Award Options [Line Items]
Award vesting period		4 years

Schedule Of Share Based Compensation Arrangements By Share Based Payment Award Options [Line Items]

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