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

Aggregate number of common shares reserved for future issuance.

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-Publisher FASB
-Name Accounting Standards Codification
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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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-Publisher FASB
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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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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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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).

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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

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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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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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Share-Based Compensation - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		39 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2018	Dec. 31, 2017
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized	2,846,681		2,846,681
Term (years)	10 years
Vesting period (years)	5 years
Share-based compensation expense	$ 572	$ 610
Tax benefit related to share-based compensation expense	$ 102	156
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized	1,138,673		1,138,673
Share-based compensation expense	$ 777	798
Tax benefit related to share-based compensation expense	$ 202	$ 305
Granted (shares)	36,500
Vested (shares)	48,749
Nonvested (shares)	695,171		695,171	730,420
Forfeited (shares)	23,000
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (shares)			40,000
Vested (shares)			12,000
Nonvested (shares)	24,000		24,000
Forfeited (shares)	2,000		4,000
Maximum \| Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Term (years)	10 years