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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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

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Unrecognized cost of unvested options awarded to employees as compensation.

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The noncash expense that represents the cost of restricted stock or unit distributed to employees as compensation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
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Number of additional shares authorized for issuance under an established share-based compensation plan.

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Gross number of share options (or share units) granted during the period.

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

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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.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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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The noncash expense that accounts for the value of stock or unit options distributed to employees as compensation.

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Stockholders' Equity - Stock Incentive Plans - Additional Information (Detail) - USD ($)	1 Months Ended	3 Months Ended		9 Months Ended		12 Months Ended
	Jul. 31, 2016	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option compensation expense				$ 48,000	$ 138,000	$ 161,000	$ 349,000
Additional compensation expense relating to stock options						55,000
Restricted stock compensation expense				84,000	228,000	266,000	$ 308,000
Additional compensation expense relating to restricted stock						$ 100,000
Stock options granted							32,765
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Remaining average recognition period for unrecognized compensation expense						1 year 1 month 13 days
Restricted stock compensation expense		$ 20,000	$ 38,000	$ 100,000	$ 200,000	$ 300,000	$ 300,000
Stock options granted				264	0
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option compensation expense		$ 3,000.0	$ 24,000.0	$ 48,000.0	$ 100,000	$ 200,000	$ 300,000
Remaining average recognition period for unrecognized compensation expense						1 year 22 days
Aggregate intrinsic value of options outstanding and exercisable						$ 0
Closing stock price (in dollars per share)						$ 0.92
Stock options granted				43	0
Stock Options [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted, term				10 years		10 years
2004 Stock Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved for the issuance (in shares)		34		34		11,719
2009 Stock Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved for the issuance (in shares)	269	573		573		200,391
Increased number of shares (in shares)	304
Shares available for grant		55		55		120,883
2009 Stock Incentive Plan [Member] \| Scenario, Previously Reported [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved for the issuance (in shares)	94,141
Increased number of shares (in shares)	106,250