The percentage of increase (decrease) in the stock-based compensation expense due to forfeitures.

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Share based compensation arrangement by share based payment award fair value assumptions annual forfeiture rate.

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No definition available.

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- Definition

Share based compensation arrangement by share based payment award fair value assumptions dividends growth rate.

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- Definition

Represents the exercise price related to equity instrument other than option related to share based compensation.

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No definition available.

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Sharebased compensation arrangement by sharebased payment award fair value assumptions weighted average expected dividend rate.

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- Definition

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

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-Publisher FASB
-Name Accounting Standards Codification
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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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- 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

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

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- Definition

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

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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Number of fully vested and expected to vest exercisable options that may be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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- Definition

Price of a single share of a number of saleable stocks of a company.

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No definition available.

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- Definition

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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Note 15 - Stock-based Compensation (Details Textual) - USD ($) $ / shares in Units, $ in Millions			1 Months Ended	3 Months Ended			12 Months Ended
	Nov. 07, 2019	May 07, 2018	May 31, 2012	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2019	Dec. 31, 2018
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total				$ 8.4			$ 8.4
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition							1 year 2 months 12 days
Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Annual Forfeiture Rate				10.70%	5.30%	1.10%
Increase (Decrease) In Stock Based Compensation Expense Due To Forfeitures, Percent				101.90%	381.80%	(89.30%)
Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Dividends Growth Rate							20.00%
Sharebased Compensation Arrangement By Sharebased Payment Award Fair Value Assumptions Weighted Average Expected Dividend Rate							0.70%
Share Price				$ 74.52	$ 52.30		$ 74.52	$ 52.30
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Number				479,402	846,215		479,402	846,215
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value							$ 19.3	$ 5.2
Weighted Average [Member]
Share Price				$ 65.04	$ 55.58		$ 65.04	$ 55.58
2012 Stock Incentive Plan [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period			6 years
2012 Stock Incentive Plan [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period			10 years
2012 Stock Incentive Plan [Member] \| Stock Options And Stock Appreciation Rights [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized			4,000,000
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period			1 year
2012 Stock Incentive Plan [Member] \| Stock Options And Stock Appreciation Rights [Member] \| Share-based Payment Arrangement, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage			25.00%
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period			24 months
2012 Stock Incentive Plan [Member] \| Stock Options And Stock Appreciation Rights [Member] \| Share-based Payment Arrangement, Tranche One [Member] \| Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage			100.00%
2012 Stock Incentive Plan [Member] \| Stock Options And Stock Appreciation Rights [Member] \| Share-based Payment Arrangement, Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage			25.00%
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period			36 months
2012 Stock Incentive Plan [Member] \| Stock Options And Stock Appreciation Rights [Member] \| Share-based Payment Arrangement, Tranche Three [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage			50.00%
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period			48 months
2012 Stock Incentive Plan [Member] \| Stock Options And Stock Appreciation Rights [Member] \| Share-based Compensation Award, Tranche Four [Member] \| Senior Management [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage			25.00%
2012 Stock Incentive Plan [Member] \| Share-based Payment Arrangement, Option [Member] \| Non Employee Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period			1 year
The 2018 Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized		5,000,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant				3,584,485			3,584,485
The 2018 Incentive Plan [Member] \| Stock Appreciation Rights and Restricted Stock Units [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period		6 years
The 2018 Incentive Plan [Member] \| Stock Appreciation Rights and Restricted Stock Units [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period		10 years
The 2018 Incentive Plan [Member] \| Stock Appreciation Rights and Restricted Stock Units [Member] \| Share-based Payment Arrangement, Tranche One [Member] \| Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage		100.00%
The 2018 Incentive Plan [Member] \| Stock Appreciation Rights and Restricted Stock Units [Member] \| Share-based Payment Arrangement, Tranche One [Member] \| Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage		50.00%
The 2018 Incentive Plan [Member] \| Stock Appreciation Rights and Restricted Stock Units [Member] \| Share-based Payment Arrangement, Tranche Two [Member] \| Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage		25.00%
The 2018 Incentive Plan [Member] \| Stock Appreciation Rights (SARs) [Member] \| Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period	6 years
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	11,495
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Exercise Price	$ 76.87
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value							$ 19.8
The 2018 Incentive Plan [Member] \| Restricted Stock Units (RSUs) [Member] \| Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	9,420
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value							$ 76.4
The 2012 and 2004 Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant				0			0