The market price at the grant date for the Performance Units granted.

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Represents the amount of difference between the fair value of the underlying shares reserved for issuance and exercise price of vested portions of options and SARs outstanding and currently exercisable.

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No definition available.

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

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No definition available.

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Represents the number of non-vested options and SARs outstanding.

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Represents the weighted average grant date fair value of non-vested options and SARs outstanding.

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As of the balance sheet date, aggregate intrinsic value of fully vested and expected to vest options and stock appreciation rights outstanding.

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Represents the number of shares into which fully vested and expected to vest stock options and SARs outstanding can be converted under the option plan as of the balance sheet date.

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No definition available.

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Represents the number of stock options and SARs that vested during the reporting period.

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No definition available.

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Represents the aggregate grant date fair value of stock options and SARs that vested during the reporting period.

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No definition available.

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Represents the high end of the range of the payout depending on the achievement of goals.

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No definition available.

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Represents the low end of the range of the payout depending on the achievement of goals.

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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).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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-Publisher FASB
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-SubTopic 10
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Percentage of vesting of award under share-based payment arrangement.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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Stock Compensation Plan (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2019
Options
Stock options and Stock Appreciation Rights vested
Options vested (in shares)				66,953
Aggregate grant date fair value of Options vested (in millions)				$ 1.0
Outstanding Stock Options and Stock Appreciation Rights
Options outstanding (in shares)				406,719	416,548
Aggregate intrinsic value (in millions)				$ 0.6	$ 3.9
Per share weighted average exercise price (in usd per share)				$ 70.59	$ 70.08
Exercisable Options (in shares)				377,517	318,029
Aggregate intrinsic value (in millions)				$ 0.6	$ 3.9
Unvested Options (in shares)				29,202	98,519
Per share weighted average grant date fair value (in usd per share)				$ 14.74	$ 14.41
Performance Share Units ("PSUs")
Additional disclosures
Granted (in shares)				27,773
Percentage of target to be awarded, low end of range (not less than)				0.00%
Percentage of target to be awarded, high end of range (not more than)				200.00%
Market price at grant date of performance units (in usd per share)				$ 71.88
Employees \| Restricted Stock Units (RSUs)
Additional disclosures
Granted (in shares)				58,587
Equity instruments other than options, weighted average grant date fair value (in usd per share)				$ 68.54
Employees \| Scenario, Forecast \| Vesting Tranche One \| Restricted Stock Units (RSUs)
Additional disclosures
Award vesting rights			33.00%
Employees \| Scenario, Forecast \| Vesting Tranche Two \| Restricted Stock Units (RSUs)
Additional disclosures
Award vesting rights		33.00%
Employees \| Scenario, Forecast \| Vesting Tranche Three \| Restricted Stock Units (RSUs)
Additional disclosures
Award vesting rights	33.00%