Number of shareholder approved company stock incentive plans.

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- Definition

Share-Based Compensation Arrangement By Share-Based Payment Award, Shares Issued In Period, Percentage

+ References

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- Definition

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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-Name Accounting Standards Codification
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- Definition

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

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- Definition

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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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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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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- Definition

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

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Number of shares authorized for issuance 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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Earnings per Share & Stock Compensation - Narrative (Details) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2020 USD ($) plan $ / shares shares	Dec. 31, 2019 USD ($) shares	Dec. 31, 2018 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of stock incentive plans \| plan	2
Compensation, nonvested awards, compensation cost not yet recognized \| $	$ 3.7	$ 3.7
Compensation, nonvested awards, cost not yet recognized, period for recognition	2 years 7 months 6 days	2 years 7 months 6 days
Anti-dilutive awards outstanding (fewer than)(in shares)	110,000	110,000	110,000
The 2005 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized for issuance (in shares)	2,880,000
The 2014 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Additional number of shares authorized for issuance (in shares)	3,000,000
Restricted Stock Units (RSUs) \| The 2005 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expiration period	10 years
Restricted Stock Units (RSUs) \| The 2014 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expiration period	10 years
Restricted Stock Units (RSUs) \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	1 year
Restricted Stock Units (RSUs) \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	4 years
Restricted Stock Units (RSUs) \| Employees And Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	96,000
Granted (in dollars per share) \| $ / shares	$ 49.02
Relative Total Shareholder Return Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	3 years
Relative Total Shareholder Return Awards \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued (as a percent)	0.00%
Relative Total Shareholder Return Awards \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued (as a percent)	150.00%
Relative Total Shareholder Return Awards \| Employees And Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	40,000
Granted (in dollars per share) \| $ / shares	$ 56.32