Amortization of non vested stock grants and performance based awards.

No definition available.

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- Definition

Share based compensation arrangement by share based payment award equity instruments other than options grants in period aggregate grant date fair value.

+ References

No definition available.

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- Definition

Amount of expense recognized from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments), awarded to key employees or individuals. Excludes amount related to plans that cover generally all employees (for example, but not limited to, qualified pension plans).

+ References

No definition available.

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- Definition

The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
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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.

+ 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).

+ References

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

+ References

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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

Number of share instruments newly issued under a share-based compensation plan.

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-Topic 718
-SubTopic 10
-Section 50
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- Definition

Number of share options (or share units) exercised during the current period.

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-Name Accounting Standards Codification
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-SubTopic 10
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Stock Based Compensation - Additional Information (Detail) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option expense	$ 0	$ 3,000	$ 0	$ 7,000
Amortization of non-vested stock grants and performance-based awards	$ 839,000	$ 1,252,000	$ 2,235,000	$ 2,748,000
Stock options exercised by employees and directors	0	71,606	0	71,606
Number of shares of non-vested stock that vested	6,752	3,762	23,573	39,953
Employees and Directors [Member] \| Non-Vested Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of non-vested stock issued			18,688
Aggregate fair value			$ 1,800,000
Employees and Directors [Member] \| Non-Vested Shares [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option plan, share based compensation, vesting period (in years)			1 year
Fair market value of the non-vested stock on the date of grant			$ 95.71
Employees and Directors [Member] \| Non-Vested Shares [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option plan, share based compensation, vesting period (in years)			7 years
Fair market value of the non-vested stock on the date of grant			$ 99.10
Chief Executive Officer, David Rogers [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense			$ 400,000