Aggregate Intrinsic Value Of Stock Options Exercisable

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Closing price of common stock.

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Employee Service Share Based Compensation Unrecognized Compensation Costs

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Employee Service Share Based Compensation Unrecognized Compensation Costs Weighted Average Period Of Recognition

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Estimated annualized forfeiture rate for options granted to employees.

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- Definition

Estimated annualized forfeiture rate for options granted to senior management.

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- Definition

Percentage Increase In Number Of Shares Available For Future Issuance Under Stock Based Awards

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No definition available.

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Issued

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No definition available.

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award Percentage Earning Of Participants

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

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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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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)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&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.

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No definition available.

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- Definition

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

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No definition available.

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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).

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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-Paragraph 2
-Subparagraph (a)(3)
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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

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-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

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- Definition

Gross number of share options (or share units) granted during the period.

+ References

No definition available.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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

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- Definition

Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

+ References

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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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(2)
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- Definition

Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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- Definition

Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 2
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- Definition

Weighted average remaining contractual term for fully vested and expected to vest options that are exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

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

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No definition available.

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- Definition

Weighted average remaining contractual term of outstanding stock options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
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Stock Based Compensation (Additional Information) (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	6 Months Ended	12 Months Ended
	Jun. 30, 2017	Jun. 30, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average exercise price, granted	$ 0.54	$ 1.15	$ 6.09	$ 21.40
Averages contractual term		10 years	10 years
Estimated annualized forfeiture rate for options granted to employees		15.00%	15.00%
Estimated annualized forfeiture rate for options granted to senior management		8.00%	8.00%
Unrecognized compensation cost		$ 713	$ 2,295
Operating expenses weighted average period		2 years 3 months 18 days	2 years 3 months 19 days
Shares subject to outstanding common stock options granted		105,000	146,000
Weighted average contractual term for options outstanding			7 years 7 days	7 years 7 months 17 days	7 years 4 months 6 days
Weighted average contractual term for options exercisable			5 years 6 months 7 days	6 years 2 months 12 days	6 years 6 months 4 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value	$ 0	$ 0	$ 0	$ 539	$ 610
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value			0	518	509
Aggregate Intrinsic Value Of Stock Options Exercisable			$ 56	$ 37	$ 13,429
Issuance of common stock in connection with employee stock purchase plan, shares			29,070
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Average vesting term		4 years	4 years
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Average vesting term		6 years	6 years
2007 Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock reserved for issuance	1,325,000	1,325,000	1,325,000
Shares subject to outstanding common stock options granted		505,000	561,000
Shares available for future grants	466,000	466,000	501,000
Vesting periods of options granted		4 years	4 years
Options expire from date of grant		10 years	10 years
Closing price of the Company's common stock	$ 0.58	$ 0.58
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity instrument granted			0	0
Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock reserved for issuance			20,930
Share Based Compensation Arrangement By Share Based Payment Award Percentage Earning Of Participants				15.00%
Share-based Compensation Arrangement by Share-based Payment Award, Purchase Price of Common Stock, Percent				85.00%
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized			12,500
Percentage Increase In Number Of Shares Available For Future Issuance Under Stock Based Awards			1.00%
Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Issued			50,000