Unrecognized cost of unvested share-based compensation awards.

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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

Amount of other expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses associated with a discontinued operation or an asset retirement obligation.

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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

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.

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No definition available.

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- Definition

The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

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- Definition

The highest quantity of shares an employee can purchase under the plan per period.

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- Definition

Number of equity instruments other than options outstanding, including both vested and non-vested instruments.

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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

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

Purchase price of common stock expressed as a percentage of its fair value.

+ References

No definition available.

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- Definition

Number of shares issued during the period as a result of an employee stock purchase plan.

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- Definition

Deferred Compensation Arrangement with Individual, Number of Plans

+ References

No definition available.

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- Definition

Deferred Compensation Arrangement with Individual, Share Equivalents Balance

+ References

No definition available.

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- Definition

Conversion unit of deferred stock units

+ References

No definition available.

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- Definition

Deferred Stock Units Payable in Cash

+ References

No definition available.

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- Definition

Reduction in number of shares available for grant for each award granted.

+ References

No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Actual Payout, Percentage

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No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Maximum Employee Subscription Rate, Amount

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No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Maximum Number of Shares per Employee per Year

+ References

No definition available.

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Stock-Based Compensation (Textuals) (Details)	12 Months Ended
Stock-Based Compensation (Textuals) (Details)	Dec. 31, 2018 USD ($) plan $ / shares shares	Dec. 31, 2017 USD ($) $ / shares shares	Dec. 31, 2016 USD ($) $ / shares shares	Dec. 31, 2015 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Other charges \| $	$ 3,800,000	$ 0	$ 200,000
Shares available for grant/issuance	3,710,483
Unrecognized compensation expense for all nonvested awards \| $	$ 19,100,000
Weighted average period for recognition	1 year 8 months
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards, expiration period	10 years
Number of shares reduced for each award granted	1
Stock Appreciation Rights (SARs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	4 years
Awards, expiration period	10 years
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding, Number	39,819	51,368	116,087	232,930
Award Types Other than Stock Options and Stock Appreciation Rights [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares reduced for each award granted	2.5
Performance-Vesting Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted at target level	102,307	92,045	115,035
Granted at target level \| $ / shares	$ 90.45	$ 84.01	$ 60.47
Employee Stock Purchase Plan (ESPP) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for grant/issuance	3,900,000
Percentage of current market price for sales to eligible employees	85.00%
Limitation on payroll deductions of employee's base salary, percent	25.00%
Limitation on payroll deductions of employee's base salary, amount \| $	$ 25,000
Maximum number of shares per employee	2,000
Maximum number of shares per employee, per year		8,000
Purchases of shares	55,669	56,218	60,839
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted at target level	15,942	0	1,393
Granted at target level \| $ / shares	$ 96.77		$ 71.79
Annual Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted at target level	1,500	1,800	2,400
Vesting period	4 years
Granted at target level \| $ / shares	$ 93.00	$ 86.93	$ 59.64
Performance-Vesting Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted at target level	560	598	419
Granted at target level \| $ / shares	$ 89.64	$ 83.47	$ 59.64
Minimum [Member] \| Performance-Vesting Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Actual payout range	0.00%
Minimum [Member] \| Performance-Vesting Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Actual payout range	0.00%
Maximum [Member] \| Performance-Vesting Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Actual payout range	200.00%
Maximum [Member] \| Performance-Vesting Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Actual payout range	200.00%
Deferred Compensation Plans [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Deferred Compensation Arrangement with Individual, Conversion Unit	1
Number of deferred compensation plans \| plan	2
Number of deferred stock units	429,777
Number of deferred stock units payable in cash	24,296
Deferred Compensation Plans [Member] \| Non-Employee Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted at target level	18,824
Granted at target level \| $ / shares	$ 87.69