Number of equity incentive plans.

No definition available.

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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
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- Definition

Amount of cash inflow from exercise of stock options granted under share-based compensation arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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-Section 45
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Balance Type:	debit
Period Type:	duration

- 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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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Balance Type:	na
Period Type:	duration

- 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.

+ Details

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- Definition

Value, before forfeitures, of stock or other type of equity granted of any equity-based compensation plan other than an employee stock ownership plan (ESOP).

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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- Details

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- Details

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Stock Options and Restricted Stock - Additional Information (Detail) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)	Jun. 30, 2017 USD ($) Incentive_Plan shares	Jun. 30, 2016 USD ($) shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of equity incentive plans \| Incentive_Plan			3
Stock options exercised, Shares \| shares			0	38,879
Proceeds from stock option exercises \| $				$ 501
Share-based compensation expense \| $	$ 500	$ 500	$ 900	700
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Market value of restricted shares granted \| $			$ 700	$ 1,900
Restricted Stock Units (RSUs) [Member] \| Executive Officers [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted common stock granted \| shares			7,434	27,077
Restricted Stock Units (RSUs) [Member] \| Non-employee Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted common stock granted \| shares			6,454	5,952