Share-based Compensation Arrangement by Share-based Payment Award, Performance Period Used In Calculation

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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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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-Section 50
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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

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-Publisher FASB
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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.

+ References

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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).

+ References

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- Definition

Per share weighted average intrinsic value of equity-based compensation awards granted. Excludes stock and unit options.

+ References

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-Publisher FASB
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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.

+ References

No definition available.

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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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.

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-Publisher FASB
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- Definition

Number of options outstanding, including both vested and non-vested options.

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Performance Incentive Plan (Narrative) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	May 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized (in shares)				1,800,000
Stock options outstanding (in shares)	0
Stock options exercisable (in shares)	0
Restricted shares granted (in shares)	40,581
Share-based compensation cost	$ 9,282,000	$ 12,971,000	$ 10,758,000
Unrecognized compensation cost	$ 11,029,000
Weighted average period for recognition of unrecognized compensation cost	2 years 3 months 18 days
Restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted shares granted (in shares)	291,281
Restricted stock \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)	3 years
Restricted stock \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)	5 years
Performance shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted shares granted (in shares)	175,626	169,495
Performance period used In calculation	3 years
Weighted average grant price (in dollars per share)	$ 37.06	$ 43.73
Fair value share price (in dollars per share)	$ 23.70	$ 25.77
Share-based compensation cost	$ 0	$ 0	$ 0