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

Amount of noncash expense for share-based payment arrangement.

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-Publisher FASB
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-Topic 230
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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.

+ 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 shares issued under share-based payment arrangement.

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- Definition

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

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Stock Based Compensation - Additional Information (Detail) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option expense	$ 0	$ 0	$ 0	$ 7,000
Amortization of non-vested stock grants and performance-based awards	$ 955,000	$ 1,456,000	$ 3,284,000	$ 4,203,000
Stock options exercised by employees and directors	6,500	0	6,500	71,606
Number of shares of non-vested stock that vested	375	11,114	23,948	51,067
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