Closing stock price on the last trading day of the year ended.

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

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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- Definition

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.

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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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No definition available.

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

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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

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

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No definition available.

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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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Percentage of vesting of award under share-based payment arrangement.

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Stock-Based Compensation Plan (Narrative) (Details) - USD ($)	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Jun. 30, 2019
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of awards	4 years
Contractual term	10 years
Aggregate intrinsic value of options exercised	$ 2,900,000	$ 100,000
Closing price per share	$ 45.52
Stock-based compensation expense recorded		$ 100,000
Remaining unamortized stock-based compensation cost	$ 0
Options granted, Number of Shares	0	0
Aggregate intrinsic value of options outstanding	$ 5,400,000
Stock Options [Member] \| Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	25.00%
Stock Options [Member] \| Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	2.083%
Stock Options [Member] \| Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of awards	1 year
Stock Options [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense recorded	$ 100,000
Restricted Stock [Member] \| Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of awards	4 years
Restricted Stock [Member] \| Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of awards	1 year
Restricted Stock and Performance Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense recorded	$ 500,000	$ 600,000
Remaining unamortized stock-based compensation cost	$ 3,800,000
Stock-based compensation cost recognition period	1 year 10 months 24 days
Restricted Stock and Performance Stock [Member] \| Employees [Member] \| Each Anniversary Of Grant Date [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	25.00%
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of awards	3 years
Stock-based compensation cost recognition period	3 years
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share authorized for issuance			250,000
Employee Stock Purchase Plan [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense recorded	$ 100,000	$ 100,000