Represents the number of shares available for grant cancelled during the period.

No definition available.

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- Definition

Represents the rollforward of Shares Available for Grant under the Plans.

+ References

No definition available.

+ 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

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)(iv)(3)
-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).

+ 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)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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

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- Definition

The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

+ References

+ 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 options outstanding, including both vested and non-vested options.

+ 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

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

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

+ 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

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

+ Details

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Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- References

No definition available.

+ Details

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- Definition

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

+ References

+ Details

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- Definition

Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

+ References

No definition available.

+ Details

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- Definition

Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

+ References

No definition available.

+ Details

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Stock-Based Compensation - Summary of Option and RSU Activity (Details) - $ / shares			1 Months Ended	3 Months Ended			12 Months Ended
	Aug. 23, 2016	Jan. 01, 2016	Jun. 30, 2014	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Shares Available for Grant
Options granted (in shares)	(334,027)
Number of Shares
Options granted (in shares)				0
Weighted Average Exercise Prices
Weighted-average exercise price (in dollars per share)	$ 7.20
Amended and Restated 2010 Equity Incentive Plan [Member]
Shares Available for Grant
Balance at the beginning of the year (in shares)				392,000	183,000
Additional shares authorized		50,000				50,000
Balance at the end of the year (in shares)				81,000	392,000	183,000
Number of Shares
Balance at the beginning of the period (in shares)				336,000	508,000
Balance at the end of the period (in shares)				248,000	336,000	508,000
Weighted Average Exercise Prices
Weighted-average exercise price (in dollars per share)				$ 16.47	$ 16.04	$ 14.06
RSU's \| Amended and Restated 2010 Equity Incentive Plan [Member]
Shares Available for Grant
Restricted stock units granted (in shares)				(407,000)
Restricted stock units cancelled and returned to Plan (in shares)				8,000	37,000	5,000
Options \| Amended and Restated 2010 Equity Incentive Plan [Member]
Shares Available for Grant
Balance at the beginning of the year (in shares)						114,000
Additional shares authorized			150,000				50,000	50,000	200,000
Options granted (in shares)						(1,000)
Options cancelled and returned to Plan (in shares)				88,000	172,000	15,000
Balance at the end of the year (in shares)							114,000
Number of Shares
Balance at the beginning of the period (in shares)						522,000
Options granted (in shares)						1,000
Options cancelled and returned to Plan (in shares)				(88,000)	(172,000)	(15,000)
Balance at the end of the period (in shares)							522,000
Weighted Average Exercise Prices
Weighted-average exercise price (in dollars per share)							$ 13.88
Options granted (in dollars per share)						$ 2.36
Options cancelled and returned to Plan (in dollars per share)				$ 14.83	$ 10.20	$ 6.94