Unrecognized cost of unvested share-based compensation awards.

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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

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- Definition

Unrecognized cost of unvested options awarded to employees as compensation.

+ References

No definition available.

+ Details

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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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585

+ Details

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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

+ Details

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- Definition

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

+ References

+ Details

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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

+ Details

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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

+ Details

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- Definition

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

+ References

+ Details

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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.

+ Details

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- Definition

The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

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- Definition

The highest quantity of shares an employee can purchase under the plan per period.

+ References

+ Details

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- Definition

Number of equity instruments other than options outstanding, including both vested and non-vested instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(ii)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

+ References

+ Details

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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

+ References

+ Details

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Period Type:	instant

- Definition

Price of a single share of a number of saleable stocks of a company.

+ References

No definition available.

+ Details

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Period Type:	instant

- 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

+ Details

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- Definition

Number of non-vested options outstanding.

+ References

No definition available.

+ Details

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- Definition

Purchase price of common stock expressed as a percentage of its fair value.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Number of shares issued during the period as a result of an employee stock purchase plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 29, 30
-Article 5

+ Details

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Number of Purchase Periods

+ References

No definition available.

+ Details

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- Definition

Share-based Compensation Arrangement By Share-based Payment Award Offering Period Term

+ References

No definition available.

+ Details

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Provision for Number of Additional Shares Authorized, Percent

+ References

No definition available.

+ Details

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- Definition

Share-based Compensation Arrangement By Share-based Payment Award, Vesting Rights Percentage

+ References

No definition available.

+ Details

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- Definition

Stock-based Compensation, Maximum Amount Deductible

+ References

No definition available.

+ Details

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- Details

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Stock-Based Compensation - Narrative (Detail)		1 Months Ended	12 Months Ended
Stock-Based Compensation - Narrative (Detail)	Dec. 03, 2013 USD ($)	Jun. 30, 2012 shares	Dec. 31, 2015 USD ($) Purchase_Period $ / shares shares	Dec. 31, 2014 USD ($) $ / shares shares	Dec. 31, 2013 USD ($) shares	Dec. 04, 2013 shares	Nov. 29, 2010 shares	Dec. 31, 2006 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average fair value of options outstanding (in usd per share) \| $ / shares			$ 17.78	$ 21.22
Common stock price (in usd per share) \| $ / shares			$ 14.74
Stock-based compensation \| $			$ 7,686,000	$ 9,492,000	$ 8,207,000
Consultants [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested stock options (in shares)			32,000
Unrecognized compensation expense \| $			$ 329,000
Stock-based compensation \| $			193,000	$ (169,000)	$ 323,000
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized compensation costs \| $			$ 10,696,000
Recognition over weighted average periods			2 years 6 months 1 day
Stock Options [Member] \| Consultants [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting term			2 years 5 months
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants in period (in shares)			147,000	0
Time-based Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants in period (in shares)			933,000
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested restricted stock outstanding (in shares)			0
Grants in period (in shares)				0
Restricted stock units vested (in shares)				165,000
Restricted stock units forfeited (in shares)				1,000
2006 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock reserved								141,750
Expected term			10 years
Nonvested shares issued			0	0
2006 Plan [Member] \| Monthly Vesting Period [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting rights percentage			2.08333%
2006 Plan [Member] \| Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting term			4 years
2006 Plan [Member] \| Stock Options [Member] \| Annual Vesting Period [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting rights percentage			25.00%
2010 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock reserved							280,459
Expected term			10 years
Vesting term			4 years
2010 Plan [Member] \| Monthly Vesting Period [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting rights percentage			2.08333%
2010 Plan [Member] \| Annual Vesting Period [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting rights percentage			25.00%
Restated 2010 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock reserved		1,162,500	324,713	369,244
Percent of additional shares authorized provision		4.00%
Inducement Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock reserved			202,230	88,562		337,500
Maximum amount deductible \| $	$ 1,000,000
Purchase Plan [Member] \| Employee Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock reserved			151,490	145,444
Percentage of purchase price			85.00%
Maximum percentage of employee withholding			20.00%
Maximum number of shares per employee			2,500
Offering period			6 months
Number of purchase periods \| Purchase_Period			2
Number of shares purchased during period			25,204	62,987	38,041
Purchase Plan [Member] \| Employee Stock [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Offering period			27 months