Share Based Compensation (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Treasury Stock Reissued Shares For Director Grants	13,400	13,450	13,500
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost	$ 1.7	$ 1.3	$ 1.3
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Number	206,827
Shares Paid for Tax Withholding for Share Based Compensation	18,436	14,038
Restricted Stock, Shares Issued Net of Shares for Tax Withholdings	29,670	30,341
Allocated Share-based Compensation Expense	$ 6.3	$ 6.0	$ 5.0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period	48,106	44,379
2013 Long Term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common shares authorized for delivery upon the exercise of incentive stock options	600,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Period Increase (Decrease)	0
2017 Employees Long Term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	750,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	450,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	61,890	62,265
2017 Employees Long Term Incentive Plan [Member] \| Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross			15,700
2017 Employees Long Term Incentive Plan [Member] \| Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	61,890	62,265	58,740
2017 Non Employee Directors LTIP [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	150,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	86,850

Common Shares Authorized for Delivery Upon the Exercise of Incentive Stock Options

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Treasury Stock Reissued Shares For Director Grants

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Number, after shares used to satisfy grantee's tax withholding obligation for award under share-based payment arrangement, of restricted shares issued. Excludes cash used to satisfy grantee's tax withholding obligation.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Number of shares authorized for issuance under share-based payment arrangement.

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

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The increase or decrease in number of shares reserved for issuance under stock option agreements awarded under the plan that validly exist and are outstanding, including vested options.

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Number of fully vested and expected to vest options outstanding that can be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Amount of cost expensed and capitalized for award under share-based payment arrangement.

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Number of shares used to settle grantee's tax withholding obligation for award under share-based payment arrangement.

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