Stock Compensation Plans - Schedule of Share-based Compensation, Stock Options, Activity (Details) - $ / shares	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	86,672	245,350	436,900	614,850
Share-based Payment Arrangement, Option, Exercise Price Range, Shares Exercisable	1,033,303	971,107	807,868	773,236
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 50.528	$ 48.079	$ 49.139	$ 43.886
Exercised
Share-based Payment Arrangement, Option, Exercise Price Range, Shares Exercisable	91,285	21,436	125,894
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 40.532	$ 33.805	$ 33.031
Forfeited from terminated plan(s)
Share-based Payment Arrangement, Option, Exercise Price Range, Shares Exercisable	5,197	6,875	17,424
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 44.563	$ 38.849	$ 44.163
Forfeited from current plan(s)
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	44,022	4,800	8,450
Share-based Payment Arrangement, Option, Exercise Price Range, Shares Exercisable	44,022	4,800	8,450
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 52.256	$ 57.513	$ 55.000
Granted from 2018 Plan
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	202,700	196,350	186,400
Share-based Payment Arrangement, Option, Exercise Price Range, Shares Exercisable	202,700	196,350	186,400
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 57.980	$ 41.740	$ 60.086

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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The number of shares reserved for issuance pertaining to the outstanding exercisable stock options as of the balance sheet date in the customized range of exercise prices for which the market and performance vesting condition has been satisfied.

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