Common Stock Redeemed For Payment of Stock Option Exercises, Aggregate Value

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- Definition

Share-Based Compensation Arrangement By Share-Based Payment Award, Number Of Compensation Plans

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

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- Definition

The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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- Definition

Amount of cash inflow from exercise of stock options granted under share-based compensation arrangement.

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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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No definition available.

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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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- Definition

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

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No definition available.

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- Definition

Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest options outstanding. 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

Percentage of vesting of share-based compensation awards.

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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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- Definition

Number of shares issued during the period related to Restricted Stock Awards, net of any shares forfeited.

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Stock-Based Compensation - Narrative (Details)	12 Months Ended
Stock-Based Compensation - Narrative (Details)	Dec. 31, 2018 USD ($) plan shares	Dec. 31, 2017 USD ($) shares	Dec. 31, 2016 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of stock-based compensation plans \| plan	2
Options expiration period	10 years
Stock option awards granted \| shares	0	0
Intrinsic value of fully-vested stock options outstanding	$ 9,000,000
Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock compensation expense	0
Tax benefits from stock-based compensation	0
Total intrinsic value of options exercised	4,900,000	$ 6,300,000	$ 5,600,000
Proceeds from Stock Options Exercised	1,800,000	2,400,000	4,700,000
Common Stock Redeemed For Payment of Stock Option Exercises, Aggregate Value	1,600,000	2,800,000	3,100,000
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock compensation expense	5,600,000	3,300,000	3,900,000
Tax benefits from stock-based compensation	$ 200,000	$ 600,000	$ 1,500,000
Stock issued during period, shares, restricted stock award \| shares	214,893
Unrecognized compensation cost related to nonvested restricted stock awards	$ 7,900,000
Unrecognized compensation cost related to nonvested restricted stock to be recognized over weighted average period (in years)	1 year 10 months 28 days
Restricted Stock \| Upon Achievement of Performance Goals
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock issued during period, shares, restricted stock award \| shares	59,464
Restricted Stock \| Upon Achievement of Defined Return on Equity Performance Goals
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock issued during period, shares, restricted stock award \| shares	29,732
Restricted Stock \| Upon Achievement of Defined Total Return to Shareholder Goals
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock issued during period, shares, restricted stock award \| shares	29,732
Restricted Stock \| Upon One-Third Annual Anniversary
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock issued during period, shares, restricted stock award \| shares	155,429
Restricted Stock \| First Anniversary
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual vesting percentage	33.33%
Restricted Stock \| Second Anniversary
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual vesting percentage	33.33%
Restricted Stock \| Third Anniversary
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual vesting percentage	33.33%
2006 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for grant \| shares	1,727,765