Represents the period over which the stock-based compensation expense is recognized by the entity.

No definition available.

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- Definition

Represents the highest amount of shares that an eligible employee can purchase under the plan per period.

+ References

No definition available.

+ Details

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- Definition

Represents the number of offering periods per annum over which an employee may purchase the shares of common stock of the entity under the stock-based compensation arrangements.

+ References

No definition available.

+ Details

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- Definition

Represents the offering period over which an employee may purchase the shares of common stock of the entity under the stock-based compensation arrangements.

+ References

No definition available.

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- Definition

Aggregate cash paid by the entity during the period to settle equity instruments granted under equity-based payment arrangements.

+ 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 (k)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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://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=6415400&loc=d3e5070-113901

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- Definition

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

+ References

No definition available.

+ Details

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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

Disclosure of the aggregate tax benefit realized from the exercise of stock options and the conversion of similar instruments during the annual period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
-Paragraph 2
-Subparagraph (j)
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- 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

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

+ References

No definition available.

+ Details

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- Definition

Number of share instruments newly issued under a share-based compensation plan.

+ 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

Intrinsic value of equity-based compensation awards outstanding. Excludes stock and unit options.

+ 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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- 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
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
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Stock-Based Compensation - Narrative (Details)			1 Months Ended			3 Months Ended			9 Months Ended		12 Months Ended
Stock-Based Compensation - Narrative (Details)	Aug. 23, 2016 shares	Jan. 01, 2016 shares	May 31, 2015 shares	Jun. 30, 2014 shares	Jun. 30, 2010 USD ($) item	Sep. 30, 2017 USD ($) shares	Mar. 31, 2017 shares	Sep. 30, 2016 USD ($)	Sep. 30, 2017 USD ($) shares	Sep. 30, 2016 USD ($) shares	Dec. 31, 2016 USD ($) shares	Dec. 31, 2015 USD ($) shares	Dec. 31, 2014 USD ($) shares
Share-based Compensation Arrangement by Share-based Payment Award, Additional General Disclosures [Abstract]
Options granted (in shares)						0
Shares issued in Replacement Offering	334,027
Options
Share-based Compensation Arrangement by Share-based Payment Award, Additional General Disclosures [Abstract]
Unamortized compensation cost, net of expected forfeitures \| $						$ 1,100,000			$ 1,100,000		$ 2,600,000
Weighted average expected period over which the expense is to be recognized									1 year 10 months 24 days		2 years 7 months 6 days
Tax benefits associated with exercise of stock options \| $						0		$ 0	$ 0	$ 0	$ 0	$ 0	$ 0
Stock options exercised									0	0
RSU's
Share-based Compensation Arrangement by Share-based Payment Award, Additional General Disclosures [Abstract]
Unamortized compensation cost, net of expected forfeitures \| $											$ 600,000
Weighted average expected period over which the expense is to be recognized									1 year 4 months 24 days		2 years
Unamortized compensation cost for awards other than options, net of expected forfeitures \| $						600,000			$ 600,000
Cash paid for employee income tax related to settlement of RSUs \| $									22,000
Total intrinsic value of the restricted stock units outstanding \| $						$ 400,000			$ 400,000
RSU's \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award, Additional General Disclosures [Abstract]
Stock-based compensation expense, recognition period									3 years
RSU's \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award, Additional General Disclosures [Abstract]
Stock-based compensation expense, recognition period									5 years
Employee stock purchase plan
Share-based Compensation Arrangement by Share-based Payment Award, Additional General Disclosures [Abstract]
Increase in number of shares reserved for issuance			200,000
Number of offering periods \| item					2
Offering period					6 months
Purchase price to be paid by participants as a percentage of price per share either at the beginning or the end of each six-month offering period, whichever is less					85.00%
Employee stock purchase plan \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award, Additional General Disclosures [Abstract]
Maximum amount of shares that eligible employee may purchase annually (in dollars) \| $					$ 25,000
Amended and Restated 2010 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Additional General Disclosures [Abstract]
Increase in number of shares reserved for issuance		50,000					50,000
Amended and Restated 2010 Equity Incentive Plan [Member] \| Options
Share-based Compensation Arrangement by Share-based Payment Award, Additional General Disclosures [Abstract]
Options granted (in shares)							1,000
Shares issued in Replacement Offering							1,000
Increase in number of shares reserved for issuance				150,000							50,000	50,000	200,000