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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Award Contractual Life

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- Definition

Share Based Compensation Percentage Of Targeted Performance Awards

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- Definition

Stock Options, Number of stock incentive plans

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

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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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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- Definition

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

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No definition available.

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Stock-Based Compensation Plans (Narrative) (Details)	1 Months Ended				12 Months Ended
Stock-Based Compensation Plans (Narrative) (Details)	May 31, 2020 shares	Feb. 29, 2020	Feb. 28, 2019	Feb. 28, 2018	Dec. 31, 2020 item shares	Dec. 31, 2019 shares	Dec. 31, 2018 shares	Mar. 31, 2021 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of stock incentive plans \| item					3
Number of shares authorized					5,100,000
Options granted					298,670	287,010	246,350
Perfromance Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares vesting period, years		3 years	3 years	3 years
Perfromance Stock Units [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage participant can ultimately receive of the targeted PSUs					200.00%
Perfromance Stock Units [Member] \| Forecast [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vested share units that will be converted								26,525
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares vesting period, years					3 years
Shares contractual life					5 years
Options granted					298,670
Stock Options [Member] \| Prior to Year 2014 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares contractual life					10 years
Outside Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted	2,511