Common stock conversion basis ratio.

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- Definition

Number of share-based compensation plans.

+ References

No definition available.

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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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- Definition

Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

+ References

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- Definition

Unrecognized cost of unvested options awarded to employees as compensation.

+ References

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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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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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 additional shares authorized for issuance under an established share-based compensation plan.

+ References

No definition available.

+ Details

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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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- Definition

The addition or reduction in the number of reserved shares that could potentially be issued under the option plan attributable to reasons other than grants, exercises, forfeitures, and expirations during the reporting period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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- Definition

Maximum number of shares that may be issued in accordance with the plan as a proportion of outstanding capital stock.

+ References

No definition available.

+ Details

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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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-Paragraph 2
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Stock Plans - Additional Information (Detail)	3 Months Ended			9 Months Ended
Stock Plans - Additional Information (Detail)	Sep. 30, 2018 USD ($) CompensationPlan shares	Mar. 31, 2018 shares	Sep. 30, 2017 USD ($) shares	Sep. 30, 2018 USD ($) CompensationPlan shares	Sep. 30, 2017 USD ($) shares	Dec. 31, 2017 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of stock-based compensation plans \| CompensationPlan	2			2
Annual increase in number of shares available for grant				500,000
Percentage of common shares outstanding				4.00%
Number of shares available for issue, additional shares		446,299
Stock options, vesting period				4 years
Stock options, expire period				10 years
Unrecognized stock-based compensation \| $	$ 299,000			$ 299,000
Stock-based compensation expense \| $				$ 86,000	$ 162,000
Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Recognized weighted-average period years				2 years 7 months 6 days
Restricted Stock Units (RSUs) and Performance Stock Units (PSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares of common stock to be received, per restricted stock unit and performance stock unit	1			1
Restricted stock units outstanding	250,000			250,000		392,659
Restricted Stock Units (RSUs) and Performance Stock Units (PSUs) Subject to Performance-based Vesting
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units outstanding	0		0	0	0
Stock-based compensation expense \| $	$ 0		$ 0	$ 0	$ 0
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized stock based compensation \| $	$ 150,000			$ 150,000
Stock Incentive Plan 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for future grants	1,545,719			1,545,719