The historical period upon which annual expected stock price volatility is based.

No definition available.

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- Definition

Represents the daily treasury yield curve period, in years, upon which the average risk-free interest rate is based.

+ References

No definition available.

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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

Amount of cost to be recognized for option under share-based payment arrangement.

+ References

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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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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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.

+ References

No definition available.

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- Definition

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iii)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

+ References

No definition available.

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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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Shareholders' Equity and Long-Term Incentive Compensation - Stock Option (Details) - USD ($) $ / shares in Units, $ in Millions						12 Months Ended
	Feb. 20, 2021	Feb. 21, 2020	Feb. 20, 2020	Feb. 22, 2019	Feb. 21, 2019	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Stock-based Compensation
Historical period upon which annual expected stock price volatility is based (years)						3 years
Maximum
Stock-based Compensation
Daily treasury yield curve period upon which average risk-free interest rate is based (years)						3 years
Minimum
Stock-based Compensation
Daily treasury yield curve period upon which average risk-free interest rate is based (years)						1 year
Stock options
Stock-based Compensation
Granted (in shares)	105,000		125,000		186,000	105,000	139,000	189,000
Exercise price per share (in dollars per share)	$ 58.34		$ 50.09		$ 36.51	$ 58.34	$ 49.57	$ 36.50
Fair value of stock option grants (in dollars per share)	$ 23.49	$ 17.40		$ 13.31
Historical period upon which annual expected stock price volatility is based (years)	6 years
Vesting period (years)	3 years
Number of stock options exercisable (in shares)						1,150,000
Compensation costs not yet recognized						$ 1.6
Stock options \| Maximum
Stock-based Compensation
Maximum contractual term (years)	10 years
Daily treasury yield curve period upon which average risk-free interest rate is based (years)	7 years
Stock options \| Minimum
Stock-based Compensation
Daily treasury yield curve period upon which average risk-free interest rate is based (years)	5 years
Stock options \| Weighted Average
Stock-based Compensation
Weighted-average period over which unrecognized compensation costs will be recognized						2 years