Stock-based Employee Compensation, Stock Option Plans, and Deferred Compensation Plan for Directors - Summary of Option Activity (Details) - USD ($)	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021
Number of Shares
Outstanding at beginning of period (in shares)	1,601,250
Granted (in shares)	248,000
Exercised (in shares)	(26,875)
Expired/Forfeited (in shares)	(19,000)
Outstanding at end of period (in shares)	1,803,375
Exercisable at end of period (in shares)	1,287,250
Weighted Average Exercise Price per share
Outstanding at beginning of period (in usd per share)	$ 51.73
Granted (in usd per share)	47.90
Exercised (in usd per share)	44.44
Expired/Forfeited (in usd per share)	51.71
Outstanding at end of period (in usd per share)	51.31
Exercisable at end of period (in usd per share)	$ 52.74
Aggregate Intrinsic Value
Outstanding at beginning of period	$ 4,886,106
Granted	0
Exercised	179,217	$ 3,450
Expired/Forfeited	0
Outstanding at end of period	0
Exercisable at end of period	$ 0

Share-based Compensation Arrangement by Share-based Payment Award, Options, Aggregate Intrinsic Value [Roll Forward]

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Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Intrinsic Value

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Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period, Intrinsic Value

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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- Definition

For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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-Section 50
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-Subparagraph (c)(1)(iv)
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Weighted average price of options that were either forfeited or expired.

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Gross number of share options (or share units) granted during the period.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested options.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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Number of share options (or share units) exercised during the current period.

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-Name Accounting Standards Codification
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